"A lot of blood," DeCosta said. "You could tell there was nothing you could do for him."
He said he also saw a woman on the floor who had been shot in the chest.
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. There was a series of rapid-fire shots in short succession as Christmas music played. Patty said he dove for the floor and then ran.
His Macy's co-worker, Pam Moore, told the AP the gunman was short, with dark hair.
Kira Rowland told KGW-TV that she was shopping at Macy's with her infant son when the shots started.
"All of a sudden you hear two shots, which sounded like balloons popping," Rowland told the station. "Everybody got on the ground. I grabbed the baby from the stroller and got on the ground."
Rowland said she heard people screaming and crying.
"I put the baby back in the stroller and ran," Rowland said.
Kaelynn Keelin was working two stores down from Macy's when the gunfire began. She watched windows of another store get shot out. She and her co-workers ran to get customers inside their own store to take shelter.
"If we would have run out, we would have run right into it," she said.
Shaun Wik, 20, was Christmas shopping with his girlfriend and opened a fortune cookie at the food court. Inside was written: "Live for today. Remember yesterday. Think of tomorrow."
As he read it, he heard three shots. He heard a man he believes was the gunman shout, "Get down!" but Wik and his girlfriend ran. He heard seven or eight more shots. He didn't turn around.
"If I had looked back, I might not be standing here," Wik said. "I might have been one of the ones who got hit."
Clackamas Town Center is one of the Portland area's biggest and busiest malls, with 185 stores and a 20-screen movie theater.
Holli Bautista, 28, was shopping at Macy's for a Christmas dress for her daughter when she heard pops that sounded like firecrackers. "I heard people running and screaming and saying 'Get out, there's somebody shooting,'" she told the AP.
She said hundreds of shoppers and mall employees started running, and she and dozens of other people were trying to escape through a department store exit.
Tiffany Turgetto and her husband were leaving Macy's through the first floor when they heard gunshots coming from the second floor of the mall. They were able to leave quickly through a Barnes & Noble bookstore before the police locked down the mall.
"I had left my phone at home. I was telling people to call 911. Surprisingly, people are around me, no one was calling 911. I think people were in shock," she said.
Associated Press writers Nigel Duara in Portland, Michelle Price in Phoenix and Manuel Valdes in Seattle contributed to this report.
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