Troutdale Police Chief Scott Anderson said that Jared Michael Padgett, 15, a freshman at Reynolds High School, was positively identified as the gunman. The victim, Emilio Hoffman, 14, was also a freshman, but investigators have not revealed any connection between the two yet.
Padgett, carrying a guitar case and duffle bag, took the school bus Tuesday morning, Anderson said. He immediately went to the locker room, where Hoffman, a junior varsity soccer player, was shot.
His coaches described Hoffman on Twitter as "a great soccer player and a great friend." A teenager Hoffman identified as his girlfriend on his Facebook page also mourned him.
"I have never been in so much pain," she said in a tweet Tuesday. "There is nothing I wouldn't give to see him again."
While Padgett's family kept their guns in a secured location, the teenager was able to bypass the security measures, Anderson said.
"The shooter used an AR-15 type rifle in the attack and carried, but did not use, a semi-automatic handgun," the chief said. "Investigators also recovered nine loaded magazines with the capability of holding several hundred rounds."
Padgett was also armed with a large knife, and was wearing a vest with storage space for ammunition.
Anderson said that Todd Rispler, a physical education teacher who was wounded in the locker room, and the police officers who responded to the school, "saved many many lives." A bullet grazed Rispler's hip.
"Mr. Rispler made his way to the office, where he was able to notify the administration, which then immediately initiated the lockdown," Anderson said.
Investigators believe Padgett shot himself after being wounded by police.