Biography of columbine shooters

Dylan Klebold and Eric Harris

At approximately 11:19 a.m., Dylan Klebold and Eric Harris, dressed in trench coats, began shooting fellow students outside Columbine High School, located in a suburb south of Denver. The pair then moved inside the school, where they gunned down many of their victims in the library.

By approximately 11:35 a.m., Klebold and Harris had killed 12 students and a teacher and wounded more than 20 other people.

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Shortly after 12 p.m., the two teens turned their guns on themselves.

Investigators later learned Harris and Klebold had arrived in separate cars at Columbine around 11:10 on the morning of the massacre. The two then walked into the school cafeteria, where they placed two duffel bags each containing a 20-pound propane bomb set to explode at 11:17 a.m.

The teens then went back outside to their cars to wait for the bombs to go off. When the bombs failed to detonate, Harris and Klebold began their shooting spree.