Columbine School Massacre

On April 20, 1999, two teenagers killed a dozen students and a teacher at the Columbine High School, and then killed themselves.

Eric Harris and Dylan Klebold carried out a massacre in the Columbine High School in Jefferson County, Colorado. 

It was the third largest school massacre in America, after the recent one at Virginia Tech and the Texas University massacre in 1966.

The event spurred discussion on the purchase of firearms and school safety.