Students, school officials and public safety huddle outside Arapahoe High School in Centennial, Colo., Friday, Dec. 13, after a shooting at the school.
The gunman who shot up a Colorado school on Friday wrote a plan for the murders on his body. He wrote the Latin phrase “alea iacta est” or “the die is cast” on his arm along with letters and numbers that may have indicated classrooms with specific targets, the Arapahoe Sheriff’s office said in a statement obtained by NBC Tuesday.
Karl Pierson, 18, allegedly entered Arapahoe High School in Centennial, Colo. with a shotgun because he was upset that he lost his spot on the debate team. He brought a .12 gauge pump action shotgun with more than 124 rounds of ammunition, three Molotov cocktails and a machete with him. He tried to seek out his speech coach — Tracy Murphy, who was also the librarian — friends and officials told NBC News.
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Pierson didn’t find Murphy — who ran outside in order to try to lure Pierson away from others in the school — but Pierson critically wounded senior Claire Davis before killing himself. Davis was shot in the head. Her family says that she is in a coma in critical but stable condition.
Police say that the markings on Pierson’s arm indicate that he may have had other targets. They “correlate directly with the identification of the library and specific classrooms located in the immediate area,” the Arapahoe Sheriff’s office said in a statement. The phrase “alea iacta est,” famously uttered by Julius Caesar after he crossed the Rubicon and committed himself to a civil war with Rome, also suggests that Pierson had carefully planned his attack.
The co-captain of the debate team, Joe Redmond, told NBC News that Pierson had sent Murphy a “death threat” and had studied the bomb-making manual Anarchist’s Cookbook, a revelation that led the author to call for it to be pulled from shelves.