Students ran, hid as gunman opened fire in Calif.

OAKLAND, Calif. — One wounded woman cowered in the bushes after the gunman opened fire on the campus of a small Christian university. One student hid in a locked classroom as the shooter banged on the door. Another heard the shots and ran to safety.

All within an hour Monday, police said, a 43-year-old former student named One L. Goh walked into Oikos University, and began a rampage that left seven people dead and three people wounded, trapped some in the building and forced others to flee for their lives.

It was an "extremely chaotic scene," police Chief Howard Jordan said.

Soon after the shooting, heavily armed officers swarmed the tiny college of fewer than 100 students in a large industrial park near the Oakland airport. For a time, police believed the gunman could still be inside. But he wasn't.

Instead, officers said he apparently drove about three miles from campus before surrendering to officers inside a supermarket.

"It's going to take us a few days to put the pieces together," said Jordan said. "We do not have a motive."

Jordan told "Good Morning America" on Tuesday that the suspect was "upset with the administration of the school" and that the suspect had been "mistreated" and "disrespected" by students.

Those connected to the school, including the founder and several students, described the gunman as a former nursing student. The chief said Goh is a South Korean national who's a former student of the university.

Police first received a 911 call at 10:33 a.m. reporting a woman on the ground bleeding. As more calls came in from the school, the first arriving officer found a victim suffering from a life-threatening gunshot wound, he said.

More officers arrived and formed a perimeter around the school on the belief that the suspect was still inside, he said.

"Potential victims remained inside the building either trapped by a locked door which officers were unable to open," Jordan said. Others were unable to flee because they were injured, he said.

Jordan said there were about 35 people in or near the building when gunfire broke out. Of the seven fatalities, five died at the scene and another two at the hospital. The wounded victims are in stable condition, and at least one person has been released from the hospital. He told GMA on Tuesday the victims ranged in age from 21 to 40.

"This unprecedented tragedy was shocking and senseless," Jordan said.

Art Richards said he was driving by the university on his way to pick up a friend when he spotted a woman hiding in the bushes. He pulled over, and when he approached her, she said, "I'm shot" and showed him her arm.

"She had a piece of her arm hanging out," Richards said, noting that she was wounded near the elbow.

As police arrived, Richards said he heard 10 gunshots coming from inside the building. The female victim told him that she saw the gunman shoot one person point-blank in the chest and one in the head.

Tashi Wangchuk, whose wife attended the school and witnessed the shooting, said he was told by police that the gunman first shot a woman at the front desk, then continued shooting randomly in classrooms.

Wangchuk said his wife, Dechen Wangzom, was in her vocational nursing class when she heard gunshots. She locked the door and turned off the lights, Wangchuk said he was told by his wife.

The gunman "banged on the door several times and started shooting outside and left," he said. Wangchuk said no one was hurt inside his wife's classroom, but that the gunman shot out the glass in the door. He said she did not know the man.

"She's a hero," he said of his wife.