The other remaining hostages escaped unharmed, and paramedics confirmed that Morrison had committed suicide shortly before police were able to enter the classroom.
Keyes was pronounced dead at 4:32 p.m. MDT (23:32 UTC) at Saint Anthony's Hospital in Denver, Colorado, after undergoing emergency surgery.
[4] At about 11:40 a.m.,[6] Morrison entered the school carrying a .40 S&W caliber Glock 22 pistol,[7] a Smith & Wesson .357-caliber revolver (which wasn't used during the incident), and a backpack, which he claimed contained "three pounds of C-4".
A search of the backpack later recovered duct tape, handcuffs, knives, a stun gun, rope, scissors, massage oil, sex toys, and numerous rounds of ammunition, but no explosives.
[1] A sixteen-year-old student named Katrina Keller reportedly saw Morrison entering the school before the time specified by police.
She stated that she had been walking past a vacant classroom and saw a man inside wearing a hooded sweatshirt, apparently angry.
Over the next several hours, four of the girls held hostage were released one at a time from the room, then escorted out of the building by SWAT and other law enforcement.
[1][12] Park County sheriff Fred Wegener (whose son was in the school building at the time of the incident)[4] informed the media that all seven girls were molested, though he did not know "how much or to what degree.
"[10] During the sexual assaults, Morrison reportedly held his gun to the hostages' heads and threatened to kill them if they did not cooperate.
[15] By the time the four student hostages were released, a bomb squad, SWAT team from Jefferson County, and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives were sent to the scene.
[1][19] After using the hostages as human shields against the Jefferson County SWAT team, Morrison shot at the policemen,[4] and then at Emily Keyes,[6] who was trying to run.
[6] Morrison had been imprisoned in 1973 for larceny and possession of marijuana, and was arrested on a separate occasion for obstructing police in Littleton, Colorado.
Morrison's family gave the letter to police, who then submitted the document to the FBI Behavioral Unit in Quantico, Virginia.
[21] In the 14-page letter, Morrison claimed that he was mentally and physically abused by his father as a child, and had suicidal thoughts since he was 21 years old.
Although an increase in communication with law enforcement was evident in the Platte Canyon High School shooting, Del Elliot of the University of Colorado noted that "[the vast majority of school districts] are so totally absorbed with CSAP and academic requirements that they aren't spending a lot of time and resources on this issue".
Park County Sheriff Fred Wegener proposed having a guard there during the school day, but he stated that that particular suggestion was outside the current budget.