OAKLAND, Calif. - A gunman opened fire at a private Christian college in Oakland on Monday, killing seven people and wounding three others before a suspect, reportedly a former student, was taken into custody, authorities said.

Oakland city officials said they believed the gunman had acted alone in the mid-morning shooting at Oikos University but did not immediately identify him and declined to offer a motive for the rampage.

The school's founder, Pastor Jong Kim, told the Oakland Tribune newspaper that the man arrested at a shopping mall about five miles from the scene had previously been a nursing student there, but was no longer enrolled.

Kim told the newspaper that he heard about 30 gunshots.

Oakland City Council President Larry Reid said at a press conference carried on local media that at least six people had been killed and three wounded. Police later confirmed that a seventh person had been killed in the shooting.

"As you may have heard, the suspected shooter in today's deadly shooting at Oikos University on Edgewater Drive is in custody, and it appears he acted alone," the city said in a brief statement.

"The surrounding area is still cordoned off, but police have advised that no imminent public safety threat appears to exist in the immediate area," it said.

Hours later, two bodies remained on a grassy area outside the school, covered by a sheet.

The shooting came just over a month after a student gunman in Ohio opened fire in a high school cafeteria, killing three students in the deadliest shooting rampage at a US high school in six years.

Oikos, which offers programs in theology, nursing, music and Asian medicine, describes itself on its website as having been started to provide the "highest standard education with Christian value and inspiration."

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