Flowers are placed in memory of Robin Williams on his Walk of Fame star in the Hollywood district of Los Angeles on Monday. Williams, the ...
In this film publicity image released by Twentieth Century Fox, Teddy Roosevelt, portrayed by Robin Williams, right, and Larry Daley, portrayed by Ben Stiller are ...
This November 9, 2009 file photo shows actor Robin Williams, right, and his wife Susan Schneider at the premiere of Old Dogs in Los Angeles. ...
Williams dressed up as a woman housekeeper in Mrs Doubtfire. One of his most popular performances ever.
Al Pacino roughing up Williams in Insomnia. The film showed Williams in a role which took him out of his comfort zone.
Williams with on-screen family in hit fantasy-thriller Jumanji.
This March 23, 1998 file photo shows Robin Williams holding his Oscar high backstage at the 70th Academy Awards at the Shrine Auditorium in Los ...
This 1987 file photo released by Touchstone Pictures shows actor Robin Williams in character as disc-jockey Adrian Cronauer in director Barry Levinsons comedy drama, Good ...
This 1982 file photo originally released by Warner Bros. Pictures shows actor Robin Williams as T.S. Garp from the film, The World According to Garp. ...
Oscar-winning actor and groundbreaking comedian Robin Williams hanged himself with a belt in his Northern California home after he had sought treatment for depression, a coroner said on Tuesday, based on preliminary findings.
Williams, 63, was found dead by his personal assistant at midday on Monday in a bedroom. He was suspended from a belt wedged between a closet door and a door frame, in a seated position just off the ground, Marin County's assistant chief deputy coroner, Keith Boyd, told a news conference.
Read Hollywood jolted by Robin Williams' death
"Mr Williams' personal assistant became concerned at approximately 11.45am when he failed to respond to knocks on his bedroom door," Boyd said.
"His right shoulder area was touching the door with his body perpendicular to the door and slightly suspended. Mr. Williams at that time was cool to the touch with rigor mortis present in his body," Boyd added.
The official preliminary cause of death was asphyxia due to hanging, he said, and conclusion of the investigation is still weeks away.
Read Depression and death: What pushes Robin Williams of this world
Officials also found a pocket knife near Williams and superficial cuts on his left wrist with dried red material that matched what was on the knife blade.
Williams had been open about his struggles with alcohol and cocaine and in the past months had entered a rehabilitation center to help him maintain sobriety. But many questions remained over what could have led him to take his own life.
WATCH: Fans gather at sets of Robin Williams's popular movies to pay tribute
Williams' publicist, Mara Buxbaum, said on Monday that he had been suffering from severe depression, and Boyd acknowledged that he had been seeking treatment without giving more details.
He was last seen alive by his wife, Susan Schneider, on Sunday night when she retired for the evening. She left the next morning around 10am, thinking that her husband was still asleep.Read Dear Robin Williams, you changed my life
Boyd would not say whether Williams had left a suicide note, nor if any drugs or alcohol were involved. The full toxicology report would take two to six weeks, he said.
In addition to his wife, Williams is survived by three grown children - daughter Zelda, and sons Zachary and Cody.
"Yesterday, I lost my father and a best friend and the world got a little grayer. I will carry his heart with me every day. I would ask those that loved him to remember him by being as gentle, kind, and generous as he would be. Seek to bring joy to the world as he sought," Zachary Williams, known as Zak, said in a statement on Tuesday.
Funeral arrangements are pending. His body has been released by the coroner in neighboring Napa County.
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The comedian's daughter, Zelda Williams, wrote in a Tumblr post that while she would "never, ever understand how he could be loved so deeply and not find it in his heart to stay, theres (sic) minor comfort in knowing our grief and loss, in some small way, is shared with millions."
Tributes poured out from actors, comedians, politicians and generations of fans, including President Barack Obama, who called him a "one-of-a-kind" actor.
A force of manic energy, Williams long ago established himself as one of the world's most beloved comedians, who took audiences on wild flights of imagination that often stressed one simple message: Carpe Diem.
His improvisational stand-up routine broke all rules, whether he was giving a comedic account of a nuclear accident in the style of Shakespeare or grabbing a camera from an audience member and pointing the lens down his pants.
Ben Affleck, whose breakthrough role came alongside Williams and Matt Damon in 1997's Good Will Hunting, for which Williams won his only Oscar, said he was heartbroken.
"Thanks chief - for your friendship and for what you gave the world," Affleck wrote on his Facebook page. "Robin had a ton of love in him. He personally did so much for so many people. He made Matt and my dreams come true. What do you owe a guy who does that? Everything."Acts of tribute
Spontaneous acts of tribute sprang up at landmarks from his career.
In Boston, scores of people jotted tributes in chalk to Williams near a bench in the lush Public Garden downtown, which was featured in Good Will Hunting.
Mourners hung signs, including "You will be missed" and "RIP Robin" on the wooden fence of the home in Boulder, Colorado, where parts of the intro credits for his breakout 1970s TV comedy, Mork & Mindy, were filmed.
On the Hollywood Walk of Fame, fans congregated around Williams' star, leaving flowers and candles to honor the actor.
Interest in his film work spiked on Tuesday, with Dead Poets Society as well as Mrs. Doubtfire and Good Morning, Vietnam making it into the Top 20 in the iTunes movie chart.