Asphyxia was named as the cause of death for Robin Williams, who hanged himself with a belt in his San Francisco Bay Area home on Monday.
Marin County Sheriff’s Lt. Keith Boyd said Williams was last seen alive by his wife Sunday night when she went to bed. She woke up the next morning and left, thinking he was still asleep.
Shortly after that, Williams’ personal assistant came to the Tiburon home and became concerned when Williams failed to respond to knocks at a door. The assistant found the 63-year-old actor dead in a bedroom and called police.
Boyd said all evidence indicates Williams, star of “Good Will Hunting,” ”Mrs. Doubtfire,” ”Good Morning, Vietnam” and dozens of other films, took his own life. But he said a final ruling will be made once toxicology reports and interviews with witnesses are complete.
The condition of the body indicated Williams had been dead for at least several hours, Boyd said. Williams also had superficial cuts on his wrist, and a pocketknife was found nearby.
Williams had been seeking treatment for depression, Boyd said. He would not say whether the actor left a suicide note.
“We still have people we want to speak with so there is some information we’re going to withhold,” Boyd said. “We’re not discussing the note or a note at this point as the investigation is ongoing.”
Marin County, Calif., investigators said that at approximately 11:55 a.m. on Monday, Marin County Communications received a 9-1-1 telephone call reporting a male adult had been located unconscious and not breathing inside his residence in unincorporated Tiburon, CA.
Officials initially said his cause of death appeared to be “suicide due to asphyxia” but cautioned that “a comprehensive investigation must be completed before a final determination is made.”
According to the Emory University School of Medicine, asphyxia literally means suffocation.
Princeton University notes that there are different ways to die from asphyxia.
“The body creates the need to breathe from the excess carbon dioxide in the lungs; the body has no way to detect the absence of oxygen. Many gases, though non-toxic, are classified as simple asphyxiants in their pure form or in high concentrations for this very reason.
“One form of asphyxiation is from entering a low oxygen atmosphere or an inert atmosphere, such as in a food oil tank that has a covering blanket of nitrogen or argon to shield the oil from atmospheric oxygen, thus absence of sufficient oxygen to sustain life, people act normally but with no warning they simply feel dizzy and then black out in a matter of seconds as the remaining oxygen in the blood stream is consumed,” it said.
“Oxygen deficient atmospheres are the basis for many single and multiple deaths occurring; the deceased will be observed lying prone in the bottom of a tank, and then the observer will rush in to rescue them, and succumb to the same effect, hence the need to vent or purge the inert gases from all tanks before entry. The use of simple asphyxiant gases, such as the inhalation of pure helium for entertainment purposes, has resulted in death and brain injury from oxygen deficiency.”
Other causes include carbon monoxide inhalation such as from a car exhaust, contact with certain chemicals, and drug overdose.
Susan Schneider, Robin Williams wife, issued a statement following the death “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,” said Schneider, 48.
Williams publicist Mara Buxbaum said in a statement that Williams was battling “severe depression.”
“This is a tragic and sudden loss,” she said. “The family respectfully asks for their privacy as they grieve during this very difficult time.”
The Associated Press contributed to this report.