Mischa Barton was reportedly hospitalized on Thursday morning after officials responded to a disturbance at her West Hollywood apartment.
People reports that officers responded to "multiple calls around 7:15 a.m.," after which they found Barton and one other person at her home before she voluntarily went to the hospital, where she was allegedly placed under mental evaluation.
"She was making incoherent statements that made absolutely no sense," a source told E! News.
The former star of "The O.C." had celebrated her birthday surrounded by friends on Wednesday night just hours before the incident.
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According to TMZ, Barton had been behaving extremely bizarrely in her backyard, where she was uttering nonsensical statements to herself about her mother being a witch, among other proclamations.
Barton was hospitalized in 2009, and later called that incident a "full-on breakdown" in an interview with People magazine.
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