(CNN) -- Oscar-winning actor and comedian Robin Williams apparently took his own life at his Northern California home Monday, law enforcement officials said. Williams was 63.
"He has been battling severe depression of late," his media representative Mara Buxbaum told CNN. "This is a tragic and sudden loss. The family respectfully asks for their privacy as they grieve during this very difficult time."
Coroner investigators suspect "the death to be a suicide due to asphyxia," according to a statement from the Marin County, California, Sheriff's office.
Williams married graphic designer Susan Schneider in Napa Valley, California, ceremony in October 2011. Schneider sent a written statement to CNN through the representative.
Williams' wife: I am utterly heartbroken Larry King: Williams was one-of-a-kind
"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.
"On behalf of Robin's family, we are asking for privacy during our time of profound grief. 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."
Word of Williams' death stunned the entertainment community Monday.
Comedian Steve Martin tweeted, "I could not be more stunned by the loss of Robin Williams, mensch, great talent, acting partner, genuine soul."
Former CNN host Larry King said he would he remember Williams as "a genuine caring guy. Not just a funny man, but a guy who cared about people."
Marin County deputies responded to an emergency call from Williams' home in unincorporated Tiburon, California, at 11:55 a.m., reporting "a male adult had been located unconscious and not breathing," the release from the sheriff said.
Williams was pronounced dead at 12:02 p.m., it said.
Williams was last seen alive at his home, where he lives with his wife, at about 10 a.m., the sheriff's statement said.
"An investigation into the cause, manner and circumstances of the death is currently underway by the Investigations and Coroner Divisions of the Sheriff's Office," the sheriff's statement said.
"Coroner Division suspects the death to be a suicide due to asphyxia, but a comprehensive investigation must be completed before a final determination is made."
An autopsy is scheduled for Tuesday, the sheriff said.
Williams made at least two trips to rehab for drug treatment, including a visit this summer, and he underwent heart surgery in 2009.
Williams, born in Chicago on July 21, 1951, studied theater at Juilliard School before taking his stand up act to nightclubs. He was cast as Mork, an alien visitor to Earth, for a 1974 episode of television's "Happy Days."
The role led to the spin-off show "Mork & Mindy," which showcased Williams' usual comic improvisation talents.
He proved his dramatic acting skills in "Good Will Hunting," a 1997 film that earned him a best supporting actor Oscar.
Williams credited the influence of Jonathan Winters' comic irreverence and quirky characters as a great influence on his comedy. The connection between the two was completed when Winters was cast as Williams' son on "Mork & Mindy."
When Winters died in 2012, Williams said he was "my idol, then he was my mentor and amazing friend." He tweeted that Winters was his "Comedy Buddha."
Williams' fans can look forward to four more movie appearances coming to theaters, including another installment in the "Night at the Museum" franchise.
The film, set for a December release, has Williams reprising the Teddy Roosevelt role he delivered in the first two comedies.