But many remembered the master of impressions on Monday for his tender portrayal in "Mrs. Doubtfire", when he played the part of a British nanny whose identity he assumed as a divorced father to be with his children.

Williams had been recently suffering from severe depression, his publicist Mara Buxbaum said in a statement, and the actor had repeatedly talked about his past struggles with alcohol.

"This morning, I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings. I am utterly heartbroken," Williams' wife Susan Schneider said in a statement.

The Marin County Sheriff's coroner's division said it suspected Williams committed suicide by asphyxia, but the cause of death is still under investigation and an autopsy will be conducted Tuesday.

The Sheriff's office said it received an emergency call about noon local time on Monday, saying Williams was unconscious and not breathing at his home near Tiburon, north of San Francisco.

Outside the family home in a neighbourhood of low-slung houses with water views, people left flowers and talked about the man who rode his bike around and had a smile and a wave for children on the street.