Mischa Barton was hospitalized on Thursday after reportedly exhibiting worrisome behavior.
Sources said neighbors called the police after the star was seen hanging over her backyard fence and rambling about her "mom being a witch" and "the world shattering."
She was wearing only a dress shirt and tie, and reportedly fell backward at one point.
"She was making incoherent statements that made absolutely no sense and she was transported to the hospital," a West Hollywood sheriff's deputy told E! News.
Barton was previously hospitalized under an involuntary psychiatric hold in 2009 after she threatened to kill herself.The actress later described the incident as a "full-on breakdown" in an October 2013 issue of People.
"It was terrifying," she told the magazine. "Straight out of 'Girl, Interrupted.' Story of my life."
"It was a train I could not get off of. When you're young, you can do it, but after a while, it's going to come crashing down on you."
Barton is best known for playing Marissa Cooper on "The O.C.," and has since appeared on "Law & Order: Special Victims Unit" and "Recovery Road."
She also competed on "Dancing with the Stars" Season 22.
