Oregon authorities released a detailed report Friday on a mass shooting at a community college that includes a six-page, typewritten "manifesto" in which the shooter critiqued the methods of other mass killers and said he was a follower of the occult.
The report came almost two years after the Oct. 1, 2015, shooting that left nine people dead and nine others injured in a classroom at Umpqua Community College in Roseburg.
It includes a lengthy transcript from an interview with the mother of shooter Christopher Harper Mercer and an explanation of his actions that he wrote the day before the shooting and left on a thumb drive for police to find.
Harper Mercer shot himself in the head after he was wounded by police. Authorities found nine guns stashed in his backpack, in a college restroom and at his home.
In the document, the 26-year-old community college student wrote that he is part of a "demonic Hierarchy" and will become a demon when he dies and return "to kill again and again" after possessing someone else.
He makes it clear that he idolizes other mass shooters and says he has studied their methods but faults them for not killing more people or for not killing police officers.
He also paints himself as a "loser," with nothing to live for and no successes in life.
"My whole life has been one lonely enterprise. One loss after another. And here I am, 26, with no friends, no job, no girlfriend, a virgin," he wrote.
"But for people like me there is another world, a darker world that welcomes us. For people like us this (is) all that's left," he wrote. "My success in Hell is assured."
The report details how Harper Mercer singled out one student early in the attack and told him he would survive if he passed an envelope to police when they arrived.
It held the thumb drive containing his so-called "manifesto," copies of newspaper articles about other high-profile mass shooters and a report on the killing of children at a Sandy Hook, Connecticut, elementary school.
Harper Mercer's mother, Laurel Harper, told police in an interview the day of the shooting that her son was "born angry" and would have fierce tantrums as a young child that required her to pin him in a "bear hug."
As a young child, he opened the door of a car while his mother was driving on a freeway and tried to jump out, she said. He was hospitalized and eventually placed on psychiatric medications, but he stopped taking the drugs when he turned 18, she said.
He pointed a gun in his mother's face after getting kicked out of U.S. Army boot camp when he was 19 or 20, she said, and watched videos of killings on a computer in his room.
Harper Mercer seemed less volatile after they moved in 2013 from California to Roseburg, a small city about 180 miles south of Portland, she said.
When she got an automated phone message about an active shooting on her son's college campus, she said she first called a hospital to see if he was there and then called the jail to see if he'd been arrested.
When Harper could not find him, she checked his room to see if his guns were missing but could not tell because his room was so messy.
At one point, officers asked if she needed anything.
She replied, "I think I need my son back. I need to understand, really why he did this. I don't. I'm guessing."
Associated Press Writer Steven Dubois contributed to this report.
Follow Gillian Flaccus on Twitter at http://www.twitter.com/gflaccus
Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.