On April 22, 1999, Eric Harris and Dylan Klebold, who had been mistreated and viciously bullied for much of their young lives, armed themselves, stormed Columbine High School and opened fire, killing and wounding as many of their tormentors as they possibly could. They ended up killing 13 people and wounding 24 others, an unfortunately low casualty rate given the amount of time and energy they had spent on planning the whole operation and gathering materials.