Marin County police said at a news conference Tuesday that Robin Williams' death is due to an apparent hanging.

Lt. Keith Boyd said that the 63-year-old actor was discovered slightly suspended with a belt around his neck, according to The Hollywood Reporter. He added that Williams was in a seated position against the bedroom door and rigor mortis had already set in.

Cut marks were found on his wrists and a pocketknife was found nearby. It appeared to have dried blood on it, which may or may not belong to Williams.

Police will continue to investigate and Boyd noted that it will take several weeks for toxicology tests to come back. His wife said she left their house about an hour and a half before he was discovered thinking he was still sleeping.

As previously reported, Williams was found unconscious and not breathing just before noon on Monday. His cause of death was suicide by asphyxiation.

"Robin Williams passed away this morning. 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," his publicist said in a statement.

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