"It suspected the death was a suicide due to asphyxia, but the cause of death remains under investigation," Marin County Sheriff's Office said, the Independent reported.
"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.” Williams's wife Susan Schneider said in a statement released on Monday night.
The star’s publicist Mara Buxbaum said Williams had recently been suffering from severe depression.
In his final posting on Instagram on August 1, Williams had wished his daughter Zelda a happy 25th birthday.