By Keith Coffman
DENVER (Reuters) - The teenage gunman who stormed a Colorado high school last week, critically wounding a classmate, intended to attack five classrooms and scrawled on his forearm the Latin phrase meaning, "The die has been cast," investigators said on Tuesday.
Karl Pierson, an 18-year-old senior at Arapahoe High School in suburban Denver, had written on his arm the numbers and letters that correlate to specific rooms in the building, Arapahoe County Sheriff Grayson Robinson said in a statement.
He also wrote on his arm the Latin phrase, "Alea iacta est," which translates into English as "The die has been cast," the sheriff said.
Investigators are looking into whether any specific individuals in those rooms may have been potential targets.
Armed with a shotgun, a machete and three Molotov cocktails, Pierson fired five shotgun rounds and ignited one of the incendiary devices when he launched the attack last Friday.
One person, 17-year-old Claire Davis, was wounded by gunfire in the 80-second rampage. She is in a coma and is in critical but stable condition, according to her family.
Davis was shot in the face at point-blank range as she sat outside the library with a friend, police said.
Pierson committed suicide inside the library as an armed deputy stationed at the school cornered him, police said.
The shooting in the Denver suburb of Centennial, occurred just 8 miles away from Columbine High School, where in 1999 two teenagers shot dead a teacher and 12 students before committing suicide.
Tuesday's disclosures back up earlier statements by Robinson that Pierson was targeting the school's debate coach and librarian, Tracy Murphy, over a dispute the pair had, but that the gunman also sought to create carnage at the 2,000-student school.
Police said in addition to his 12-gauge pump-action shotgun, Pierson had 125 rounds of steel-shot, buckshot and slug ammunition on a bandolier or in a backpack he was carrying.
"Although it currently appears that the shooter acted alone, the ongoing investigation will include consideration of any individual who may have provided any form of assistance regarding the tragic incident," the sheriff said.
Pierson's parents said in a statement released on Monday that they were "shattered and devastated" by their son's actions.
"We cannot begin to understand why Karl did what he did," the statement said.
(Editing by Edith Honan and Andrew Hay)