It was the first of two deadly shootings that shocked America last week, but hours after the shooting at Clackamas Town Center, clues started coming together.
As the country tried to figure out why someone would bring a gun to a mall and kill two people, Jacob Roberts' roommate picked up the phone and called the police tip line, according to court documents obtained Monday by KPTV.
Christopher Darhens told Detective Geoff Erichsen that Roberts had been acting "weird" and selling his possessions on Craigslist, according to the search warrant.
Darhens also told police he had seen ammunition for an AR-15 in the home he shared with Roberts and that the 20-year-old was wearing all black when he left in his Volkswagen Jetta that morning and never returned.
The Jetta was located Tuesday night in the Clackamas Town Center parking lot.
As for the gun used in the attack, police believe he stole it from a friend who lives just a few blocks away from Roberts.
Roberts' friend, Sean Cates, told police the gunman spent his last night alive hanging out at the home he rents on Southeast 67th Avenue.
Cates told police Roberts had said he "needed a gun and needed to get out of town," according to the search warrant.
When Cates awoke the next morning, Roberts had vanished, along with Cates' AR-15 semiautomatic rifle.
The rifle found at the scene was registered to Cates, who had purchased it legally.
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