At least two people were killed when a masked gunman opened fire at a mall in the western US state of Oregon, sparking panic before apparently turning the gun on himself, police said.
At least one person was also injured in Clackamas, south of Portland, a sheriff's spokesman said, after local media reported a gunman wearing body armor opened fire with a semiautomatic rifle near a Macy's department store.
The gunman was wearing a kind of hockey mask and shouted "I am the shooter" as he moved through the mall, KGW television cited witnesses as saying.
"I can confirm that we believe at this point that there was one and only one shooter involved, and that that shooter is deceased," said Clackamas County Sheriff's Office spokesman James Rhodes.
"The shooter is dead of an apparently self-inflicted gunshot wound," he told reporters.
"In addition, we have at least one patient who was taken from the mall with a traumatic injury, and at least two that were deceased, in addition to the shooter."
The Oregonian newspaper cited a staff member, sports columnist John Canzano, as saying he heard as many as 60 shots fired while he was shopping at the mall, which would have been packed with pre-Christmas shoppers.
A large number of emergency vehicles converged on the mall, which was sealed off as nearly 100 officers moved in to secure the scene, looking for people who had hidden or who might be injured.
"We are almost finished searching the entire mall," said Rhodes at a new briefing about three hours after the shooting. Police responded to the scene after receiving multiple 911 emergency calls around 3:30 pm (2330 GMT).
Witnesses described chaotic scenes.
"A bunch of people were screaming and running by and kind of in a panic and they were yelling that there was a shooting," a man who gave his first name as Sam told KGW.
A correspondent for the TV station cited another witness as saying the gunman was wearing a white mask and body armor, and was carrying an assault rifle.
"It was shot after shot after shot after shot, like a massacre. It was the scariest thing I've ever seen," witness Kira Rowland, who was at the mall with her six-month-old baby son, told KGW.
"I'm really freaking out right now," she added. "We just ran like hell. Everybody was just screaming."