21h 45min, apr 20, 1999 y - Columbine High School Massacre
Description:
Two heavily armed students killed 12 students and a teacher. They had also wounded 24 other students. The Aftermath of this tragedy had called for schools across the nation to install metal detectors and other security measures. Many schools instituted new anti-bully policies and "zero tolerance" approaches to school violence.
Added to timeline:
The new D&F policies (1980-2012)
Date:
