Oregon Mall Shooting Update: Gunman ID'd as Jacob Tyler Roberts, 22, said to use stolen rifle

(CBS/AP) PORTLAND, Ore. - Police have identified the gunman who allegedly shot two people to death before killing himself at a suburban Oregon mall as 22-year-old Jacob Tyler Roberts, a resident of southeast Portland, CBS affiliate KOIN reports.

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Clackamas County Sheriff Craig Roberts identified Roberts as the shooter during a press conference Wednesday morning. The sheriff said Roberts used a stolen AR-15 semiautomatic rifle in the shooting, which he took from someone he knew.

The two victims who died in Tuesday's attack at the Clackamas Town Center mall were identified as 54-year-old Cindy Ann Yule and 45-year-old Stephen Matthew Forsyth, according to KOIN. A third shooting victim, Kristina Shevchenko, remains in serious condition at Oregon Health & Science University.

KOIN reported that Roberts was wearing a hockey-style mask and a load-bearing vest while carrying several fully-loaded magazines. Authorities said they are unsure how many shots were fired.

The sheriff said the rifle jammed during Roberts' attack, but he managed to get it working again. Authorities don't  have a motive for the attack.

Roberts did not have a criminal record, a law enforcement official told The Associated Press under condition of anonymity.

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