Photos: Shooting at Arapahoe High School in Centennial

Mourners visit the memorial for shooting victim Claire Davis along a fence outside Arapahoe High School in Centennial on Dec. 22, the day after her death. Photo by Jamie Cotten, Special to The Denver Post ( 032113_CD23CITIZENSCI__JC25749 )

Danielle Arno, a graduate of Arapahoe High School who knew Claire Davis, mourns the death of the 17-year-old shooting victim on Dec. 22 near a memorial along a fence outside AHS in Centennial. Photo by Jamie Cotten, Special to The Denver Post ( 032113_CD23CITIZENSCI__JC25805 )

CENTENNIAL, CO. - DECEMBER 21: A family stood in the snow reading the comments left at the memorial for Claire Davis Saturday night. A steady stream of people payed their respects at the fence outside Arapahoe High School as news spread that Claire Davis passed away Saturday night, December 21, 2013. Photo By Karl Gehring/The Denver Post ( CD21CLAIRE )

CENTENNIAL, CO. - DECEMBER 21: Thousands of comments have been left at the memorial to Claire Davis. A steady stream of people payed their respects at the fence outside Arapahoe High School as news spread that Claire Davis passed away Saturday night, December 21, 2013. Photo By Karl Gehring/The Denver Post ( CD21CLAIRE )

CENTENNIAL, CO. - DECEMBER 20: Mark Goncalves attended a candlelight vigil for Claire Davis with his daughters Angela, left, and Julia, right. Reverend Bradley Stoltenow led a candlelight vigil for Claire Davis at Shepherd of the Hills Lutheran Church December 20, 2013. Photo By Karl Gehring/The Denver Post ( CD20TEACHEREVALS )

CENTENNIAL, CO. - DECEMBER 20: Scores of persons, including Angela Goncalves, signed a card for Claire Davis following a candlelight vigil Friday night. Reverend Bradley Stoltenow led the candlelight vigil for Claire Davis at Shepherd of the Hills Lutheran Church December 20, 2013. The church is located just a block from Arapahoe High School and was one of the locations that students were led following the shooting last week. Photo By Karl Gehring/The Denver Post ( CD20TEACHEREVALS )

CENTENNIAL, CO. - DECEMBER 20: About a hundred people gathered for a candlelight vigil for Claire Davis inside Shepherd of the Hills Lutheran Church Friday night, December 20, 2013. Photo By Karl Gehring/The Denver Post ( CD20TEACHEREVALS )

Seniors Lexi Barrent, right, and Melissa Tombaugh embrace at the tribute area before entering Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. Lexi said, "I'm a little nervous, you have to get used to it again." The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW11611 )

Arapahoe High School sophomore Sarah Slack visits the tribute area outside the school in Centennial, CO December 18, 2013. Faculty and staff were allowed to return to the school to retrieve belongings left in the building. Students will be allowed to return for scheduled 2 hour periods on Thursday and Friday. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121813_ARAPAHOE_CW29155 )

Two women approach the entrance to Arapahoe High School in Centennial, CO December 18, 2013. Faculty and staff were allowed to return to the school to retrieve belongings left in the building. (Photo By Craig F. Walker / The Denver Post) ( 121813_ARAPAHOE_CW28450 )

Arapahoe High School freshman Abbie Naumann reads a note on the fence outside the school in Centennial, CO December 18, 2013. She says she is looking forward to returning to the school on Friday and seeing her classmates, "I'm excited to see my family. We've always been a family." Faculty and staff were allowed to return to the school to retrieve belongings left in the building. (Photo By Craig F. Walker / The Denver Post) ( 121813_ARAPAHOE_CW29087 )

Two women embrace outside the entrance to Arapahoe High School in Centennial, CO December 18, 2013. Faculty and staff were allowed to return to the school to retrieve belongings left in the building. (Photo By Craig F. Walker / The Denver Post) ( 121813_ARAPAHOE_CW28648 )

Two women embrace outside the entrance to Arapahoe High School in Centennial, CO December 18, 2013. Faculty and staff were allowed to return to the school to retrieve belongings left in the building. (Photo By Craig F. Walker / The Denver Post) ( 121813_ARAPAHOE_CW28155 )

Seniors gather outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29426 )

A group of students pray outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW11655 )

Senior Hannah Eddy joins classmates at the tribute area outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29933 )

A group of students embrace at the tribute area outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors will return to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW11760 )

Senior Lily Boettcher, right, is comforted by graduate Joy Dafoe outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. Lily said, "it was good to be back in the school with everybody. I love my school so much. I couldn't ask for a better community. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW11787 )

A student sits outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW20029 )

A pair of students hold hands as they depart Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29852 )

Senior Mat Lowe lights a candle at the tribute area before visiting Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29232 )

Seniors Amanda Bridges, right, and Melissa Tombaugh make their way to the tribute area before visiting Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. Melissa said, "it's rough, I'm a little nervous." The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29292 )

A student carries her belongings through a parking lot at Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29564 )

Seniors gather outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29744 )

Senior Jake Mazer says a prayer outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW29881 )

Senior Lily Boettcher, right, is comforted by graduate Joy Dafoe outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors returned to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. Lily said, "it was good to be back in the school with everybody. I love my school so much. I couldn't ask for a better community. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW20226 )

A woman has a message written on her car outside Arapahoe High School in Centennial, CO December 19, 2013. Seniors and Juniors will return to the school for two hour periods Thursday, Sophomores and Freshmen will return on Friday. The victim from Friday’s shooting at Arapahoe High School, Claire Davis, 17, remains in critical condition. She was shot on Friday when classmate Karl Pierson opened fire in the school. The gunman died from a self-inflicted gunshot wound. (Photo By Craig F. Walker / The Denver Post) ( 121913_ARAPAHOE_CW20273 )

A sign of support for shooting victim Claire Davis is woven into a fence around Arapahoe High School in Centennial, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ28867 )

Members of Grace Chapel in Englewood pray outside Arapahoe High School in Centennial, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ29317 )

Arapahoe High School cancels classes until after the new year, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ28892 )

A sign of support is woven into a fence around Arapahoe High School in Centennial, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ28786 )

Nicki Winingham and her son Logan, 14, a freshman at Arapahoe High School, pray together at a tribute on a fence near the school in Centennial, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ29307 )

Arapahoe High School cancels classes until after the new year, December 16, 2013. The school was the scene of a shooting on Friday that left a student gunman dead and two other students injured. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ28807 )

Reflecting off an advertisement at a bus stop across the street from Arapahoe High School in Centennial, local and national media are seen outside the school, December 16, 2013. This is the third school shooting in Colorado. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ28941 )

Arapahoe High School senior Melissa Tombaugh, 18, left, is comforted by her mother Jeannette, right, at a tribute set up for shooting victim Claire Davis along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_HHR_3945 )

Kristen Wallace, 17, a takes a moment to pray at a tribute set up for shooting victim Claire Davis along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_4313 )

Students, friends and family arrive at Arapahoe High School for a prayer circle on the track of the school to pray for shooting victim Claire Davis in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school and remains in critical condition. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_4382 )

A tribute for shooting victim Claire Davis is set up along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_4988 )

Friends and students take a moment to pray at a tribute for shooting victim Claire Davis set up along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_4846 )

Students, friends and family arrive at Arapahoe High School for a prayer circle on the track of the school to pray for shooting victim Claire Davis in Centennial, CO on December 15, 2013. Students from the high school attended the prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school and remains in critical condition. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_4609 )

Friends and students take a moment to pray at a tribute for shooting victim Claire Davis set up along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_5114 )

Friends and students take a moment at a tribute to pray for shooting victim Claire Davis set up along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_HHR_3854 )

Arapahoe High School senior Melissa Tombaugh, 18, gets comforted by her mother Jeannette, right at a tribute set up to pray for shooting victim Claire Davis along Dry Creek road near Arapahoe High School in Centennial, CO on December 15, 2013. Students from the high school attended a prayer service to pray for the recovery of Davis who was shot during the recent shooting at the high school. (Photo By Helen H. Richardson/ The Denver Post) ( cd15SHOOTING_DSC_5074 )

Hundreds of Arapahoe High School students gathered for a candlelight vigil Saturday night to share their prayers for Claire Davis who was shot inside the school Friday, December 13, 2013. The vigil was held at Arapaho Park in Centennial, not far from the school. Photo By Karl Gehring/The Denver Post ( CD13ARAPAHOE )

CENTENNIAL, CO. - DECEMBER 14: An investigator works at Arapahoe High School in Centennial, CO December 14, 2013. Student Karl Pierson carried a shotgun into Arapahoe High School and asked where to find a specific teacher then opened fire on Friday, wounding two fellow students before apparently killing himself, Arapahoe County Sheriff Grayson Robinson said. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW19836 )

Photo of Claire Davis. Provided by Arapahoe County Sheriff's Office.

Hundreds of Arapahoe High School students gathered for a candlelight vigil Saturday night to share their prayers for Claire Davis who was shot inside the school Friday, December 13, 2013. The vigil was held at Arapaho Park in Centennial, not far from the school. Photo By Karl Gehring/The Denver Post ( CD13ARAPAHOE )

A small group of Arapahoe High School students listened to Sheriff Grayson Robinson's press conference on the north lawn of the school Saturday afternoon. Photo By Karl Gehring/The Denver Post ( CD13ARAPAHOE )

Arapahoe High School students Avery Griggs, 16, and Joe Redmond, 18, embrace while talking about the shooting at Arapahoe High School in Centennial, CO December 14, 2013. Both students were on the debate team with the gunman as Karl Pierson and Griggs is friends with shooting victim Claire Davis. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW27391 )

A members of the Arapahoe County Sheriff's department talks with people in a parking lot at Arapahoe High School in Centennial, CO December 14, 2013. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW27026 )

Arapahoe High School sophomore Avery Griggs, 16, talks about the shooting at Arapahoe High School in Centennial, CO December 14, 2013. Griggs was on the debate team with the gunman as Karl Pierson and and friends with shooting victim Claire Davis. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW27419 )

People were allowed to pick up cars from the parking lot at Arapahoe High School in Centennial, CO December 14, 2013. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW26870 )

Sean Sweeney stops during a morning drive to say a prayer at Arapahoe High School in Centennial, CO December 14, 2013. He said,"I wanted to say a prayer for the community, the shooter and the victims. I hope teens learn from this. I just wanted to say a prayer." (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW19592 )

A sign asking for donations hangs at an entrance to Arapahoe High School in Centennial, CO December 14, 2013. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW19469 )

A members of the Arapahoe County Sheriff's department secures a parking lot outside Arapahoe High School in Centennial, CO December 14, 2013. (Photo By Craig F. Walker / The Denver Post) ( 121413_ARAPAHOE_CW27088 )

From the 2012 Arapahoe High School Year Book

Karl Pierson from the 2012 Arapahoe High School Year Book.

HIGHLANDS RANCH, CO. - DECEMBER 13: Local and federal agents went into a home in Highlands Ranch connected to the Arapahoe High School shooting Friday night, December 13, 2013. The house at 9116 S. Sugarstone Circle is where authorities believe Karl Pierson lived with his mother. (Photo By Karl Gehring/The Denver Post) ( CD13ARAPAHOE )

HIGHLANDS RANCH, CO. - DECEMBER 13: An Alcohol, Tobacco and Firearms officer brought a dog into a home in Highlands Ranch that is connected to the Arapahoe High School shooting Friday night, December 13, 2013. The house at 9116 S. Sugarstone Circle is where authorities believe Karl Pierson lived with his mother. (Photo By Karl Gehring/The Denver Post) ( CD13ARAPAHOE )

HIGHLANDS RANCH, CO. - DECEMBER 13: An Alcohol, Tobacco, and Firearms agent ducked beneath police tape outside a home in Highlands Ranch connected to the Arapahoe High School shooting Friday night, December 13, 2013. The house at 9116 S. Sugarstone Circle is where authorities believe Karl Pierson lived with his mother. (Photo By Karl Gehring/The Denver Post) ( CD13ARAPAHOE )

CENTENNIAL, CO. - December 13: (center) Jenni Meyers 17 year old senior is comforted by her older sister Mary Myers (left) and mom Julie as they leave Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11342 )

CENTENNIAL, CO. - December 13: 16 year old junior Shayna is held tightly by her father Dave Keese as they leave Shepherd of the Hills church after she was released during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11285 )

CENTENNIAL, CO - Students with their arms up are escorted to the football field after being evacuated fro the school. At a about 12:30 pm a student was spotted inside Arapahoe High School carrying a shotgun December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. DECEMBER 13: (John Leyba, The Denver Post) ( ARAPAHOESHOOTING_2JL3548 )

CENTENNIAL, CO. - December 13: Leaving the Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11265 )

CENTENNIAL, CO. - December 13: Leaving Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11507 )

CENTENNIAL, CO. - December 13: Officers in the parking lot as kids are bussed to Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11489 )

CENTENNIAL, CO. - December 13: Jenni Meyers 17 year old senior is comforted by her older sister Mary Myers after being released from Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11372 )

CENTENNIAL, CO. - December 13: 15 year olds (left) Aili Miyake and her best friend Kasina Wootten leave with Kasina's father Chris Wootten from the Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11477 )

CENTENNIAL, CO. - December 13: Kids being bussed to Shepherd of the Hills church during a lockdown when a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11464 )

CENTENNIAL, CO - A student leaves Euclid Middle School with their parents after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL4157 )

HIGHLANDS RANCH, CO - DECEMBER 13 : Law enforcement officials train spotlights at the home of the school shooting suspect on Friday, December 13, 2013. (Photo By Cyrus McCrimmon/The Denver Post) ( ARAPAHOEHSSHOOTING )

LITTLETON, CO. DECEMBER 13: Aerial view of Arapahoe High School in Centennial, Colorado, December 13, 2013.(Photo by Hyoung Chang/The Denver Post) ( Arapahoe_ShootingHC2_0404 )

LITTLETON, CO. DECEMBER 13: People line up outside of Euclid Middle School, one of the reunification centers, following a shooting incident at Arapahoe High School in Centennial, Colorado December 13, 2013. (Photo by Hyoung Chang/The Denver Post) ( Arapahoe_ShootingHC1_0553 )

LITTLETON, CO. DECEMBER 13: People line up outside of Euclid Middle School, one of the reunification centers, following a shooting incident at Arapahoe High School in Centennial, Colorado, December 13, 2013. (Photo by Hyoung Chang/The Denver Post) ( Arapahoe_ShootingHC1_0561 )

LITTLETON, CO. DECEMBER 13: School bus parked by Euclid Middle School building one of the reunification centers following a shooting incident at Arapahoe High School in Centennial, Colorado, December 13, 2013.(Photo by Hyoung Chang/The Denver Post) ( Arapahoe_ShootingHC1_9350 )

CENTENNIAL, CO - DECEMBER 13: A mother hold on to her son outside, Shepherd of the Hills School, where frightened parents were asked to pick up their children after a gunman opened fire at Arapahoe High School, December 13, 2013. One student was critically wounded. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ27416 )

CENTENNIAL, CO - DECEMBER 13: Police, on the roof, continue to search the school, where a gunman opened fire at Arapahoe High School, December 13, 2013. One student was critically wounded. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ27491 )

CENTENNIAL, CO - DECEMBER 13: Students and their parents leave Shepherd of the Hills School where frightened parents pick up their children after a gunman opened fire at Arapahoe High School, December 13, 2013. One student was critically wounded. (Photo by RJ Sangosti/The Denver Post) ( SCHOOLSHOOTING_RJ27416 )

CENTENNIAL, CO. - December 13: Students with hands behind their heads in line to be searched before joining others waiting to be bussed to their release points from the high school sports area after a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11078 )

CENTENNIAL, CO. - December 13: Students with hands behind their heads in line to be searched before joining others waiting to be bussed to their release points from the high school sports area after a student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA11066 )

CENTENNIAL, CO. - December 13: A student carried a shotgun into Arapahoe High School and opened fire on Friday, wounding two fellow students before apparently killing himself December 13, 2013 Centennial, CO. (Photo By Joe Amon/The Denver Post) ( CD13schoolshooting_JA10700 )

CENTENNIAL, CO - A student leaves Euclid Middle School with her parents after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3924 )

CENTENNIAL, CO - A student leaves Euclid Middle School with her parents after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3891 )

CENTENNIAL, CO - Bianca Britz, Freshman at Arapahoe gets a hug from her dad Stephin Britz as they leave Euclid Middle School after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3835 )

CENTENNIAL, CO - A student leaves Euclid Middle School with her parents after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3855 )

CENTENNIAL, CO - Sam Gardinier, Jr at Arapahoe High School leaves Euclid Middle School with his parents Tom and Chris Gardinier after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3770 )

CENTENNIAL, CO - A student gets a hug at Euclid Middle School after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3796 )

CENTENNIAL, CO - A student leaves Euclid Middle School with her parents after getting bused their from Arapahoe High School December 13, 2013. A gunman at the school was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3777 )

CENTENNIAL, CO - Students on their phones to their parents as they stand out side on the football field after a gunman was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3652 )

CENTENNIAL, CO - Students load up on a bus as they were taken to Euclid Middle School in Littleton. A gunman made his way to Arapahoe High School looking for a teacher December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. DECEMBER 13: (John Leyba, The Denver Post) ( ARAPAHOESHOOTING_2JL3691 )

CENTENNIAL, CO - Students hug as they stand out side on the football field after a gunman was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3666 )

CENTENNIAL, CO - Parents stand along the tennis court fence hoping to see if their child is standing out side on the football field after a gunman was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. DECEMBER 13: (John Leyba, The Denver Post) ( ARAPAHOESHOOTING_2JL3575 )

CENTENNIAL, CO - Students embrace as they stand out side on the football field after a gunman was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_2JL3632 )

CENTENNIAL, CO - Parents check their phone hoping to get a text from their child. Students who were able to get out were standing out side on the football field. A gunman, who was student at the school was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. DECEMBER 13: (John Leyba, The Denver Post) ( ARAPAHOESHOOTING_2JL3583 )

CENTENNIAL, CO - DECEMBER 13: A student is stopped by an officer from looking for her parents as students stand out side on the football field after a gunman was spotted inside Arapahoe High School December 13, 2013. The gunman was targeting a teacher at the school. The gunman shot two students in the process and then turned the gun on himself. (Photo by John Leyba/The Denver Post) ( ARAPAHOESHOOTING_1JL4257 )

LITTLETON, CO - DECEMBER 13 : At the school shooting at Arapahoe High School in Littleton, CO on Friday, December 13, 2013 Chris Foster hugs his daughter Devan Foster a senior after they reunited at the Kings Sooper parking lot. (Photo By Cyrus McCrimmon/The Denver Post) ( ARAPAHOEHSSHOOTING )