One of the most well-known cases concerning the effects of peer victimization is the Columbine High School massacre of 1999 in Columbine , Colorado , United States . The perpetrators of this incident , Eric Harris and Dylan Klebold , murdered 12 students and 1 teacher and also injured 21 other students before committing suicide . After the tragedy , details emerged showing that Harris and Klebold had been bullied for years by classmates , with little to no intervention by school officials . Though such events are not frequent , they do alarming damage
Columbine High School massacre
Columbine High School massacre
Peer victimization