Seven people were killed and three injured when a gunman went on a shooting rampage at a private California religious college near San Francisco, police said.
The suspect -- a local ethnic Korean resident who surrendered soon after the attacks -- stood up in a classroom at Oikos University in East Oakland and shot one person at point blank range in the chest, then sprayed the room with bullets, a witness recounted.
The gunman, described as looking "crazy," then allegedly went on a shooting spree through the Christian college, where victims were found in a number of locations when officers arrived after being alerted by a string of 911 calls.
Police did not immediately say what type of firearm the shooter used, or if he used multiple weapons.
Some 35 people were in or near the building at the time. Of those, 10 were hit and five were pronounced dead at the scene. Two others died later in hospital.
Survivors were later found hiding in locked classrooms and offices.
"There are seven (families) now that are having to deal with this horrendous act," Oakland City Council president Larry Reid told CNN.
"Our police department right now is doing their work and trying to understand what in fact was his motive to come and take the lives of seven individuals, and then also to leave three individuals wounded," he said.
The gunman was detained near a Safeway supermarket in the neighboring city of Alameda, where he had fled after the massacre, said Oakland police chief Howard Jordan.
"The suspect, who is believed to be an Oakland resident, surrendered to officers of the Alameda Police Department," he said. "He actually commandeered a victim's car, and drove it to Alameda," he added.
Jordan said the suspect was believed to be a former student at the college, with no previous criminal record.
"He is a Korean national," Jordan said, without specifying if he was from South or North Korea, and gave his name as One Goh, age 43.
South Korea's Yonhap news agency, citing officials at the South Korean consulate in San Francisco, identified the shooter as Ko Won-Il.
Yonhap also said the alleged shooter is a US citizen of Korean descent.
Police described the suspect as "male, Asian, heavy build, khaki clothing."
Lisa Resler, 41, said she was leaving the Safeway supermaket in Alameda with her daughter when she saw a young Asian man wearing a hat being confronted by store security. She described him as looking "very sedated" as he was handcuffed.
Within minutes of the mid-morning shooting, SWAT teams took position around the building, some smashing glass with sledgehammers and rushing inside as officers helped students evacuate the campus, the San Francisco Chronicle reported.
Angie Johnson, 52, said she saw a young woman leaving the building with blood coming from her arm and crying, "I've been shot, I've been shot."
The wounded woman said the shooter was a man in her nursing class who rose up and shot one person in the chest, then began firing wildly in the classroom, Johnson told the Chronicle.
"She said he looked crazy all the time," Johnson said, quoting the victim. "But they never knew how far he would go."
The female victim "had a hole in her right arm the size of a silver dollar with blood coming down," Johnson said.
Five ambulances were rushed to a "multi-patient medical scene," the Oakland Fire Department said on its Twitter feed.
City Council president Reid said the motive for the killings was unclear. "That information will come out during the legal process that he now finds himself in," he said.
The school says on its website that it strives to "provide highest standard education with Christian value and inspiration."
Oikos University "has a very specific goal and mission to offer education programs in the area of religious studies, music, and vocational nursing," it said.
"We motivate, educate and equip students in such a way that they will be able to live an enriched life by fulfilling their goals in life and serve the community with their learned professions and skills."