Mischa Barton has been hospitalised in LA.
Police arrived at the actress' home at 3pm on Wednesday and took her to a doctor.
Her rep told People: "Mischa has been hospitalised per the recommendation of her doctor and is resting in the hospital."
He also told the website that the police were called to protect the star from the media as she was transported to her doctor.
An LAPD Officer told People: "We assisted her with a medical issue and removed her from her home."
The officer added that no paramedics were involved and no arrests were made, but confidentiality laws prevent her from revealing details about why the 23-year-old is in hospital.
Sky Showbiz has contacted Mischa's reps and are awaiting further comment.
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