ABOVE: Watch Lt. Keith Boyd of the Marin County Sheriff’s Office share details about the death of Robin Williams. WARNING: Some viewers may find the details disturbing. Discretion is advised.
TORONTO — Actor and comedian Robin Williams was found dead in a bedroom of his California home just before 12 noon local time Monday with a belt around his neck, investigators revealed Tuesday.
A preliminary investigation indicates his death was the result of asphyxia due to hanging.
Williams was 63.
Marin County Sheriff’s Office spokesperson Lt. Keith Boyd told reporters Williams’ body was discovered by his personal assistant who grew concerned after the star did not respond to knocks on his bedroom door.
Investigators also found superficial wounds on Williams’ wrist and a pocket knife nearby with what appeared to be dried blood.
An official cause of death will come following the results of toxicology tests, which can take from two to six weeks.
Boyd would not reveal if Williams left a note but said the actor had been seeking treatment for depression.
Williams was last seen alive by his wife Susan Schneider at around 10:30 p.m. on Sunday. She left the couple’s home Monday morning to run errands assuming Williams was still asleep.
“I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings,” said Schneider, in a statement. “I am utterly heartbroken.”
She said she hopes “the focus will not be on Robin’s death, but on the countless moments of joy and laughter he gave to millions.”
READ MORE: Stars react to the death of Robin Williams
“Robin Williams passed away this morning,” confirmed the star’s rep, Mara Buxbaum, in a statement late Monday.
“He has been battling severe depression of late. This is a tragic and sudden loss. The family respectfully asks for their privacy as they grieve during this very difficult time.”
Williams had public battles with addiction throughout his career. In the late 1970s and early ’80s he was using cocaine but said he gave it up after the death of his friend John Belushi.
He went to rehab in Oregon in 2006 to deal with an alcohol problem.
This past July, Williams sought further treatment for his alcohol problem at the Hazelden Addiction Treatment Center in Minnesota.
In 2009, Williams was hospitalized for heart surgery.
Known for his manic stand-up comedy, Williams had small TV roles before a recurring guest role on Happy Days as Mork from Ork lead to a hit spinoff series of his own, Mork & Mindy. It ran for four seasons.
“It is unimaginable that this incredible human being — incredible, delicate funny dramatic human being — is gone,” Henry Winkler, who played the Fonz on Happy Days, said on CNN.
He branched out into movies, starring in films as diverse as Popeye and the World According to Garp.
SEE MORE: 5 memorable Robin Williams movie roles
Williams, who attended the Toronto International Film Festival in 1999 and 2004, made a dozen movies in Canada, including three Night at the Museum films, Man of the Year, RV, Jumanji, Death to Smoochy and Good Will Hunting. The latter earned him an Oscar for Best Supporting Actor in 1998.
He also had Oscar nods for his work in The Fisher King, Dead Poets Society and Good Morning, Vietnam.
Williams collected two Emmy Awards, four Golden Globes, two Screen Actors Guild Awards and five Grammys during his career.
WATCH: Do we need to know all the details about Robin Williams suicide?
Williams had a one-man stage show and also appeared both on and Off-Broadway.
He worked in Vancouver on Night at the Museum: Secret of the Tomb and was scheduled to reprise his gender-bending role in a Mrs. Doubtfire sequel.
His last TV series was the comedy The Crazy Ones opposite Sarah Michelle Gellar.
Williams was a key performer in the Comic Relief shows to benefit homeless charities.
The funny man was also a supporter of Robert F. Kennedy’s annual celebrity ski fundraiser in Alberta and was often seen snowboarding on the slopes of Sunshine Village.
BELOW: A series of makeshift memorials sprang up overnight at the houses used for exterior scenes on Mork and Mindy and in the blockbuster film Mrs. Doubtfire, as well as at the actor’s California home.
“He was a genuine caring guy,” said Larry King on CNN on Monday night. “He contributed a lot to charity. He was always caring and wonderful. Very friendly, very open.
“He’s a one-of-a-kind. You will not see his likes again.”
Williams leaves behind his third wife, Susan Schneider, whom he married in 2011.
His second wife, Marsha Garces filed for divorce in March 2008. The couple has two children — Zelda, 25, and Cody, 22.
Williams also has a son, 31-year-old Zachary, with first wife Valerie Velardi.
His last Instagram post was a photo of himself with daughter Zelda.
A week earlier, he posted this photo:
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