Celebrity Coroner: Robin Williams Death Ruled Suicide by Asphyxiation Authorities confirm that the Oscar winner hanged himself at his Tiburon, California, home Monday morning By Michelle Tauber Michelle Tauber Twitter Michelle Tauber is the Senior Editor overseeing Royals coverage at PEOPLE. She has been covering the royal family for PEOPLE since 2000, including William and Kate's wedding, Meghan and Harry's wedding and the births of the royal children. Formerly PEOPLE's first and only Head Writer, she has written a record-breaking 250+ cover stories spanning celebrity, crime and human interest. A graduate of the University of Florida, she lives in Orlando. People Editorial Guidelines Published on August 12, 2014 02:25 PM Share Tweet Pin Email Photo: Press Association/AP Robin Williams‘s cause of death was suicide by asphyxiation, authorities in Marin County, California, have confirmed. In a press conference held Tuesday by local law enforcement and the coroner’s office in the San Francisco Bay area, authorities revealed that the Oscar winner, who died Monday at age 63, hanged himself in his Tiburon, California, home. He was found in his bedroom on Monday by his personal assistant before a 911 call was placed at 11:55 a.m., according to Lt. Keith Boyd, assistant deputy chief coroner of the Marin County Sheriff’s Office. Williams was found “clothed, slightly suspended in a seated position” and unresponsive with a belt around his neck, said Boyd, with the other end of the belt closed in the closet. His left wrist had several acute, superficial cuts, and a pocket knife was found nearby. Williams’s assistant called 911 and “was distraught and indicated that it was an apparent suicide due to a hanging and that rigor mortis had set in,” said Boyd. Williams was pronounced dead by firefighters at 12:02 p.m. Boyd declined to answer questions regarding whether a note was found or there were any signs of drugs or alcohol. The full forensic examination and toxicology results will be available in approximately two to six weeks, he said, with the final cause of death not available until then. Boyd also noted that the actor had been undergoing treatment for depression. Williams was last seen alive by his wife, Susan Schneider, at approximately 10:30 p.m. on Aug. 10. She returned to the home soon after he was found. The actor, who most recently starred in the CBS sitcom The Crazy Ones, had checked himself into rehab in early July after battling alcohol and drug addiction throughout his life. The star had been battling severe depression, Williams’s rep said after the death. Hollywood Reacts to Robin Williams’s Death Williams had been a consummate pro on the set of The Crazy Ones, which was canceled in May after one season. “We knew he was struggling,” a source who worked with him on the series tells PEOPLE in this week’s cover story. PHOTOS: Remembering Robin Williams – His Life and Legacy The source recalls filming a scene when “his face changed. He looked so exhausted and profoundly, deeply sad. And then one minute later he pulled himself back together and nailed the scene.” For more on Robin Williams’s tragic death and his legacy as a comic genius, pick up the latest issue of PEOPLE, on newsstands Friday Robin Williams Dies at 63 If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255). The Williams family is asking well-wishers to send contributions to charities close to the actor’s heart in lieu of flowers. Suggested organizations include St. Jude Children’s Research Hospital, Challenged Athletes, USO, the Muhammad Ali Parkinson Center, the Christopher and Dana Reeve Foundation and Glide Memorial Church in San Francisco. Want more stories like this? Sign up for our newsletter and other special offers: sign me up Thank you for signing up!