RICHMOND (CBS SF/BCN) — Investigators found human remains Wednesday on a boat that caught fire Sunday night and sank at the Bethel Island Marina, a Contra Costa County sheriff’s spokesman said.

Fire crews responded around 10 p.m. Sunday to the marina on a report of a boat on fire, arriving to find the vessel covered in flames that were spreading to a dock awning, East Contra Costa Fire Protection District Battalion Chief Craig Auzenne said.

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Firefighters extinguished the blaze but learned a man lived on the boat and his vehicle was still parked at the marina. The roof and walls on part of the boat collapsed in on itself, and the boat itself ended up sinking around 1 a.m. Monday, Auzenne said.

Authorities from multiple agencies worked to raise the boat from the water, and on Wednesday sheriff’s detectives and county coroner’s officials were able to board the vessel and found the human remains there, sheriff’s spokesman Jimmy Lee said.

The coroner’s office has not identified the man as of Thursday morning.

The cause of the fire is under investigation and no oiled wildlife were reported as a result of the sunken boat, according to the California Department of Fish and Wildlife’s Office of Spill Prevention and Response.

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