(PORTLAND, Ore.) -- A masked gunman who opened fire Tuesday in the crowded Clackamas Town Center mall in suburban Portland, Ore., killing two individuals before killing himself, has been "tentatively" identified by police, though they have not yet released his name.
The shooter, wearing a white hockey mask, black clothing and a bullet proof vest, tore through the mall around 3:30 p.m., entering through a Macy's store and proceeding to the food court and public areas spraying bullets, according to witness reports.
Police have not released the names of the deceased. Clackamas County Sheriff's Office spokesman Lt. James Rhodes said authorities are in the process of notifying victims' families.
A third victim was transported to a local hospital, according to Clackamas County Sheriff Craig Roberts.
Nadia Telguz, who said she was a friend of the injured victim, told ABC News affiliate KATU-TV in Portland that the woman was expected to recover.
"My friend's sister got shot," Teleguz told KATU. "She's on her way to (Oregon Health and Science University hospital). They're saying she got shot in her side and so it's not life-threatening, so she'll be OK."
Witnesses from the shooting rampage said that a young man who appeared to be a teenager ran through the upper level of Macy's to the mall food court, firing multiple shots, one right after the other, with what is believed to be a black, semi-automatic rifle.
More than 10,000 shoppers were at the mall during the day, police said. Roberts said that officers responded to the scene of the shooting within minutes, and four SWAT teams swept the 1.4 million-square-foot building searching for the shooter. He was eventually found dead -- an apparent suicide.
"I can confirm the shooter is dead of an apparent self-inflicted gunshot wound," Rhodes said. "By all accounts there were no rounds fired by law enforcement today in the mall."
Roberts said more than 100 law enforcement officers responded to the shooting, and at least four local agencies were working on the investigation, including the FBI and Bureau of Alcohol, Tobacco and Firearms, which is working to trace the shooter's weapon.
"For all of us, the mall is supposed to be a place where we can take our families, especially during the holiday season," Roberts said. "Things like this are not supposed to happen."
Roberts also said that shoppers, including two emergency room nurses and one physician who happened to be at the mall, provided medical assistance to victims who had been shot. Other shoppers helped escort individuals out of the mall and out of harm's way, he said.
"There were a huge amount of people running in different directions, and it was chaos for a lot of citizens, but true heroes were stepping up in this time of high stress," Roberts said. "E.R. nurses on the scene were providing medical care to those injured, a physician on the scene was helping provide care to the wounded."
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