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SAN RAFAEL, Calif. (AP) — Sheriff's officials say Robin Williams committed suicide by hanging himself at his San Francisco Bay Area home.

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Marin County Sheriff's Lt. Keith Boyd on Tuesday released details about the actor and comedian's death the day before at his Tiburon home.

Sheriff's officials said Monday a preliminary investigation determined the cause of death was suicide due to asphyxia. Williams was 63 and had suffered for years from periodic bouts of substance abuse and depression.

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Williams' press representative Mara Buxbaum said the actor had been battling severe depression recently. Just last month, Williams announced he was returning to a 12-step treatment program.

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Coroner's officials say he was last seen alive at home around 10 p.m. Sunday.