Two people have been killed and one seriously injured by a gunman wearing body armour and a white mask at a shopping centre in Oregon.
Witnesses said there was chaos and disbelief as the gunman fired an initial round of bullets and then several more near the Portland mall's food court.
Police say he apparently killed himself afterwards.
Clackamas County Sheriff's spokesman James Rhodes said: "I can confirm that we believe at this point that there was one and only one shooter involved and that shooter is deceased.
"In addition to that 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."
Department store worker Austin Patty, 20, said he saw a man in a white mask carrying a rifle and wearing a bulletproof vest.
He heard the gunman say "I am the shooter" before a series of shots were fired in quick succession.
Holli Bautista, 28, said she was shopping at Macy's for a Christmas dress for her daughter when she heard loud bangs that sounded like fireworks.
"I heard people running and screaming and saying 'Get out, there's somebody shooting'."
Shaun Wik, 20, from Fairview, said he was shopping for Christmas with his girlfriend when he heard three shots.
He said a man he believes was the gunman shouted "get down", but the pair ran and did not turn around.
"If I had looked back, I might not be standing here," he said. "I might have been one of the ones who got hit."