Tributes are pouring in for American actor-comedian Robin Williams, who was found dead of an apparent suicide Monday at his California home. He was 63.

A statement from his publicist said he had been battling depression. Williams' longtime struggle with drugs and alcohol was well-known. Just last month, he admitted himself into a rehabilitation facility to help maintain his sobriety.

During his decades-long career in television and movies, Williams entertained fans of all ages. He won acclaim for numerous films, including Mrs. Doubtfire, Good Morning, Vietnam and Good Will Hunting, which earned him the Academy Award for Best Supporting Actor in 1998.

President Barack Obama praised Williams as a "one of a kind" performer who touched "every element of the human spirit."

Williams' fellow actors, friends and fans took to Twitter to share their memories. Steve Martin, who co-starred with Williams in Waiting for Godot, wrote that he "could not be more stunned" by the loss, calling Williams a "great talent, acting partner" and a "genuine soul."

Local authorities say they believe Williams killed himself by asphyxia, but the cause of death is still under investigation. An autopsy is scheduled for Tuesday.

TV debut

Born in Chicago in 1951, Williams was a stand-up comedian when he made his television debut in the late 1970s, playing an alien in the situation comedy Mork and Mindy.

Williams also acted on Broadway and continued performing stand-up comedy even after becoming a movie star, delighting audiences with his rapid-fire, improvisational routines.  

Academy Award-winning director Steven Spielberg, who directed Williams in the 1991 film "Hook," described the comedian as "a lightning storm of comic genius."

Outside Williams' home in the town of Tiburon, north of San Francisco, people left flowers, with the entertainer's neighbors praising him for his niceness.

The late actor's wife, Susan Schneider, released a statement saying, "As he is remembered, it is our hope the focus will not be on Robin's death, but on the countless moments of joy and laughter he gave to millions."

In addition to his wife, Williams is survived by his three adult children.

VOA's Mike O'Sullivan contributed to this report from Los Angeles

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