LOS ANGELES, California (X17online) - Mischa Barton has been involuntarily placed in the psychiatric ward of Cedars-Sinai Hospital by the Los Angeles Police Department.

The former O.C. star has been placed on a 5150 hold.

"She has been dealing with a lot of personal issues," a friend tells People magazine.

Barton has been spotted club hopping in L.A. and London the past few months. "I don't know if she really ever gave up some of the bad habits that had gotten out of control a couple years back."

In 2007, Barton was arrested for DUI, marijuana possession and driving without a license.

According to Barton's publicist, the actress called authorities on Wednesday to help her with a "medical problem" and is now "resting at the hospital."

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