Their actions, it was claimed, were a bloody revenge upon the high school ‘jocks’ who bullied and taunted them. Within 24 hours, the two teenagers were labelled as outcast goths and members of a gang dubbed the ‘Trench Coat Mafia’. In the aftermath of the tragedy, wild speculation circulated as to possible motivations for Harris and Klebold’s murderous spree. READ THIS: The ever-changing faces of Marilyn Manson At approximately 12:08, the two boys turned their guns on themselves, their suicides ending what was, at that point, the deadliest school shooting in American history. Within an hour, they had murdered 12 students and one teacher, and injured 24 others. When the bombs placed in the lunch hall failed to explode, the two teenagers calmly walked through the school, firing indiscriminately at students and staff. Shortly after 11am on the morning of April 20, 1999, Harris and Klebold set their plan in motion. “I want to leave a lasting impression on the world.” “It’ll be like the LA riots, the Oklahoma bombing, WWII, Vietnam, Duke and Doom all mixed together,” Harris wrote. In anticipation of the emergency services arriving, devices hidden in the boys’ cars in the school parking lots would be primed to explode, causing further devastation. The pair intended to set off homemade explosives in the school’s cafeteria at peak lunch hour, then shoot, stab and bomb any survivors. The following April, Harris promised, he and his friend Dylan Klebold aimed to “kick natural selection up a few notches” by detonating “fire bombs, chlorine gas bombs and smoke bombs” at Columbine High School.

That plan was first sketched out in his journal entry for April 26, 1998. No-one then had stumbled upon the journal entries in which Harris outlined in forensic detail his plot to murder almost everyone at his high school.

Harris’ probation officer had hailed the teenager as “a very bright individual who is likely to succeed in life” and his family were delighted when he applied to join the United States Marine Corps. But, despite his arrest in January 1998 for stealing computers from a locked van, there were signs that the young man was turning his life around. The 18-year-old hadn’t always found life easy since his family had relocated to Colorado after his Air Force pilot father retired from military service.

Eric Harris was meticulous about maintaining journals, notebooks and blogs, filling them with his musings, reflections on the past and plans for the future.

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