Columbine shooting, 20 years later: Survivors and father of victim reflect on tragedy

On April 20, 1999, two gunmen killed 12 students and one teacher at Columbine High School in Littleton, Colorado. Nearly 20 years later, we asked members of the Columbine community – Amy Over, Kacey Johnson, and Tom Mauser, father of Daniel – to write letters to their younger selves and reflect on the two decades since the shooting.

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