Researchers also called for improved data collection on mass shootings.
Teens Robert and Michael Bever reportedly planned to kill as many people as possible after stabbing five of their family members to death.
Know the signs of an individual who might act out immediately – or weeks or years from now – so you can address student, teacher and staff challenges, as well as prevent violence on campus.
Three teachers and two students at South Pasadena High School were specifically named as targets.
The suspects allegedly studied the Columbine mass shooting so that they could become the most notorious mass murderers of all time.
Police officers should have the ability to quickly stack, flow into a room, hold a position and back-clear or secondary search several rooms.