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

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.

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.

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

Canadian comics react to Williams' passing

Stand-up star Russell Peters posted a message on Twitter saying Williams' death if not just a "big loss for not just the entertainment world but for the whole world."

T-V-comic Colin Mochrie tweeted that Williams was a "very funny and lovely man."

Actor-comedian Brent Butt tweeted he was "stunned" at the news and recalled Williams showing up at Vancouver comic clubs and got the crowd roaring with laughter.

Butt said Williams used to drop in and perform at UrbanWell & Punchlines.

Comic and T-V actor Shaun Majumder said in an email that Williams helped mould his comedic instincts from a young age.

Bruce Hills, the chief operating officer of the Just for Laughs international comedy festival in Montreal, calls Williams' death "so sad on so many fronts."

Stand-up comic Frank Spadone says it is a "sad day" for comedians everywhere.

Police say a preliminary investigation indicates Williams death was a suicide due to asphyxia.

With files from The Canadian Press