Anthony J. Causi / Splash News 1 / 15
Anthony J. Causi / Splash News 1 / 15

LOS ANGELES (AP) -- Police are searching for a man convicted of threatening to kill Madonna, who walked away from a Los Angeles-area mental hospital last week.

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Los Angeles police say Robert Dewey Hoskins left a state hospital where he had been committed last year.

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Police said in a news release issued Thursday that the 54-year-old is "highly psychotic" and can be extremely violent and should not be approached by members of the public.

Hoskins served a 10-year prison sentence for stalking and threatening Madonna, and court records show he was convicted of vandalism in July 2011. The singer testified against him during his 1996 trial.

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Police say they have searched areas where Hoskins may try to go, including the city of Long Beach, which is south of Los Angeles.