Discuss as:

Oregon mall gunman identified; sheriff says he acted alone but motive unknown

Police are investigating why 22-year-old suspected gunman Jacob Tyler Roberts opened fire on people in a Portland, Ore., mall with a semi-automatic rifle. NBC's Mike Taibbi reports.

UPDATED at 3:21 p.m. ET: The masked gunman who killed two people and wounded a third at an Oregon mall packed with holiday shoppers before committing suicide was identified Wednesday as Jacob Tyler Roberts, 22.

The Portland, Ore., man opened fire with an AR-15 semi-automatic rifle that he had stolen Tuesday from a person he knew, Clackamas County Sheriff Craig Roberts said at a morning news conference.

“At this time we do not understand the motive of this attack,” Roberts said, adding that the suspect acted alone and apparently did not know any of his victims.

Jacob Tyler Roberts is suspected of killing two people at an Oregon shopping mall. NBC's Jay Gray reports.

The sheriff said that the shooter’s rifle jammed at one point during the Tuesday afternoon attack at a food court on the upper level of the Clackamas Town Center outside Portland. The suspect was able to fix the weapon and began firing again.

It’s not known how many shots were fired in the mall, which was teeming with as many as 10,000 people, many of them shopping for Christmas gifts. The sheriff said Roberts was carrying several fully loaded magazines.

After shooting his victims, the gunman walked down a stairway to the mall’s lower level, where he fatally shot himself, the sheriff said.

Authorities said Roberts had no significant criminal history. The Oregonian reported that he had two speeding tickets earlier this year.

Killed in the attack were Steven Mathew Forsyth, 45, of West Linn, and Cindy Ann Yuille, 54, of Portland. Forsyth owned a business at the mall, said Sgt. Adam Phillips.

Kristina Shevchenko, 15, of Portland, was wounded. She was struck by several bullets and was in serious condition Wednesday at Oregon Health & Science University Hospital after undergoing surgery, the hospital said.

“This was a sole person acting on his own by all indicators we have at this point,” Phillips said.

Courtesy Shevchenko family

Kristina Shevchenko was wounded in the attack Tuesday at Clackamas Town Center.

“There were no indicators that this was going to happen.”

The sheriff said authorities searched the suspect’s home and car, which was parked outside the mall, after the shooting. He wouldn’t disclose what was found.

A woman who referred to herself as Jacob’s mother said she is “very sad” and “sorry” about his actions. Tami Roberts provided a hand-written note to reporters via a friend, KATU reported.

“Tami Roberts wishes to express her shock and grief at the events at Clackamas Town City (sic) on Tuesday,” the note said. “She has no understanding or explanation for her son’s behavior and requests that her privacy be respected.”

Friends told KATU that Tami Roberts is technically Jacob's aunt, although she raised him.

Authorities said the shooter parked his car outside the mall Tuesday afternoon and hurried in on foot toward the food court on the upper level of the 1.2 million-square-foot shopping center. He was wearing a load-bearing vest and his face was covered with a hockey-style mask.

“He had a mission set forth to really take the lives of people within that mall,” Sheriff Roberts said earlier Wednesday.

Witnesses described a scene of chaos and panic that ensued, and some said they heard the gunman announce, “I am the shooter,” before he began randomly spraying bullets.

"All of a sudden, I just heard a series of gunshots … boom, boom, boom, boom, boom … whatever the shooter was shooting at, they continued to shoot," shopper Bill Hoff told NBC station KGW.

Mira Sytsma told NBC’s Matt Lauer she was walking toward a store near the food court when she heard the first shots go off.

“After the first couple of shots I had a feeling I knew what was happening,” she said.

Girl, 15, shot in Oregon mall cheats death twice

Kelly Lay was in the food court when he heard “two loud booms,” he told Lauer. Glancing to his left, he saw people running in panic. He ducked and hid behind a pillar, where two elderly women – including one in a wheelchair – had already taken shelter.

“As soon as I heard bullets hitting behind me, the wall, seeing it hit the tiles, basically the food signs above… and seeing the tiles break around me, I kind of got in fear and scared for my life,” Lay said.

He saw people running toward the exit and told the women to do the same. After helping the woman in a wheelchair, Lay took off running.

Sytsma saw one of the gunman’s victims lying on the ground about 50 feet away from where she stood by a kiosk. Turning her head away from the victim, she caught a glimpse of the shooter.

“I couldn’t really see his eyes,” she said. “I felt like I looked right at him and it was pretty scary to see him face to face like that.”

Witnesses Kelly Lay and Mira Sytsma recount the terrifying moments when a man opened fired at Portland-area mall, killing two before turning the gun on himself.

Sytsma and three other women ran for cover inside a store.

People in line to get their photos taken with Santa immediately dove for cover, KGW reported, while others hid in break rooms and bathrooms.

The mall Santa, Brance Wilson, said he was about to invite the next child onto his lap when the shots rang out upstairs. He said he instead dove for the floor and kept his head down.

"I heard two shots and got out of the chair. I thought a red suit was a pretty good target," said the 68-year-old Wilson, The Associated Press reported.

Sheriff Roberts said his department's thoughts and prayers went out to the victims and their families.

"For all of us, the mall is supposed to be a place we can all take our families, feel comfortable, this is the holidays … these things are never supposed to happen. We have a young lady at the hospital fighting for her life right now," he said.

The sheriff said the first officers arrived about a minute after the first 911 call and immediately formed teams to try to contain the shooter rather than waiting for a SWAT squad.

He said casualties were low in part due to an overwhelming police response and because the suspect’s rifle jammed at one point, though he was able to get it working again.

Also, the sheriff noted, “Clackamas Town Center had a lockdown procedure for this type of incident and they did a great job implementing that program.”

“We rehearse for these things all the time,” said Dennis Curtis, the mall’s general manager.

“Basically in a situation like this it’s either stay where you’re at and lock yourself down or get to the nearest exit and get out of the building.”

The sheriff also credited people in the mall with helping other in a time of panic and danger.

“Ten-thousand people in the mall at one time kept a level head,” Roberts said. “They got themselves out of the mall. They helped others get out. There are just a number of heroes that took the time to help people get out, whether it’s (a person) in a wheelchair or a child.”

Clackamas County Sheriff Craig Roberts discusses the gunman who opened fire at a Portland-area mall, saying it "looked to be a random shooting."


More content from NBCNews.com:

Follow US news from NBCNews.com on Twitter and Facebook