Updated: 12/15/2013 12:58 PM
Created: 12/14/2013 4:58 PM KSTP.com
By: Megan Stewart
Authorities say a teenager who wounded a fellow student before killing himself at a suburban Denver high school entered the building with a shotgun, a machete, three Molotov cocktails and ammunition strapped to his body.
Arapahoe County Sheriff Grayson Robinson says it appears 18-year-old Karl Pierson intended to track down a librarian who had disciplined him. But the librarian, who coached the school's speech and debate team, was able to escape the school unharmed.
Robinson says investigators believe Pierson made some kind of threat in September, after being disciplined.
Pierson fired a round down a hallway, then shot a fellow student who just happened to be sitting nearby with a friend as he headed toward the library. The victim, 17-year-old Claire Davis, was shot in the head at point-blank range and remains hospitalized in critical condition.
Robinson says Pierson set off one of the incendiary devices, but killed himself just one minute and 20 seconds after entering the building because he knew a sheriff's deputy assigned to the school was closing in.
Based on Pierson's arsenal, Robinson believes the teen intended to hurt many others at the school.
Pierson legally purchased his shotgun at a local store a week before the shooting and bought the ammunition the day of the shooting.
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