PORTLAND, Ore. - A gunman opened fire in a Portland-area shopping mall Tuesday, killing two people and wounding one as people were doing their Christmas shopping, authorities said.

Witnesses described a scene of chaos and disbelief as a gunman wearing some sort of camouflage outfit and what looked like a hockey mask fired rounds from a military-style rifle near the food court at Clackamas Town Center.

Parents with children joined other shoppers rushing to stores' back rooms for safety as teams of police officers began entering the mall to find the shooter.

Clackamas County Sheriff's Lt. James Rhodes said later that the gunman was dead, apparently from a self-inflicted gunshot wound. A shopper told KATU-TV he saw a man lying on the floor with a gun next to him.

Authorities went store to store to confirm that there was only one shooter and to escort hiding shoppers outside, Rhodes said.

Austin Patty, 20, who works at Macy's, 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," as if announcing himself, Patty said. He then fired several shots paced seconds apart.

A series of rapid-fire shots followed. Patty said he ducked to the ground and then ran.

His Macy's coworker Pam Moore told the Associated Press the gunman was short, with dark hair, and dressed in camouflage.

"I heard about 20 shots and everyone hit the ground," Moore said. "That's when we all just ran."

Witnesses said the mall's Santa Claus was among those who ducked for cover.

The mall is one of the Portland area's busiest. It's in a middle-class area that has become popular with families as falling real estate prices have put its homes just a few miles from downtown Portland within financial reach.

The mall has about 185 stores and a 20-screen movie theater. Sheriff's deputies said it would remain closed during the investigation of the shooting, but it wasn't clear how long that would take.

Kaelynn Keelin was working two stores down from Macy's when the gunfire began and watched windows to another store get shot out.

She and her Made in Oregon coworkers ran to get customers inside the store, Keelin said.

"We got lucky we stayed in," she said. "If we would have run out, we would have run right into it."