LOS ANGELES — The gunman who killed four people in a shooting rampage that ended at Santa Monica College on Friday had suffered from mental health issues, CNN reported.
Two years ago, he was hospitalized for treatment after allegedly talking about harming someone, a law enforcement official with knowledge of the investigation told CNN.
It's not clear how he was committed or under what circumstances he was released.
His identity has yet to be released by police.
On Friday night, Santa Monica police revised the death toll in the massacre to five, including the gunman, down from seven earlier.
According to the Los Angeles Times, conflicting witness accounts caused the discrepancy. Officials added that one of the victims remains hospitalized in critical condition.
"It's a horrific event, and everyone wishes it hadn't happened," Santa Monica Police Sgt. Richard Lewis said at a news conference Friday night.
Lewis also confirmed a "person of interest," who was taken into custody earlier in the day, "has been released and is not a suspect".
The violent massacre just west of Los Angeles appears to have started at a nearby home, where two bodies were found and the gunman allegedly set on fire.
The California Highway Patrol said the gunman then began moving along a nearby street, shooting at a bus and several cars, KTLA reported.
The gunman then opened fire on a sport-utility vehicle leaving Santa Monica College, killing the driver and injuring two passengers, The Associated Press reported.
He continued onto campus, shooting a woman on campus before firing rounds from an assault rifle in the campus library.
In a staff parking lot, college employee Joe Orcutt told the AP he saw the gunman standing calmly with his weapon, looking as though he was trying to determine which people to shoot at.
"I turn around and that's when he's just standing there, like he's modeling for some ammo magazine," he said. "He was very calm just standing there, panning around, seeing who he could shoot, one bullet at a time, like target practice."
Police eventually shot and killed the gunman on campus, according to the Times.
The campus of Santa Monica College, where students are taking final exams this week, and area schools were put on lockdown, according to CBS News.
President Barack Obama was 10 minutes away at a fundraising event at the Santa Monica home of former News Corp. President Peter Chernin when the shooting occurred, according to Reuters, but the incident appeared to be unrelated to his visit.
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