PITTSBURG (CBS SF) — The search for the body of a Fairfield father who was believed to have drowned trying to save his son will begin anew Monday morning in the waters off of the Pittsburg Marina.

The Pittsburg Police Department said they received a call about 5:30 p.m. Saturday reporting a man missing in the Sacramento River.

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Police Sergeant Tony Turnbull said a 52-year-old Fairfield man had jumped into the river to rescue his son who had fallen out of a boat without a life jacket on. The boy was rescued by others, but the father disappeared under the water and has not been seen since.

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The Contra Costa Sheriff’s Office, Contra Costa Fire, and the Coast Guard responded and searched for the man before suspending operations Saturday night. On Sunday, the search resumed but the man was not located.

Authorities said search teams would be back in the waters on Monday to resume their search.

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The boy was taken to a hospital and treated for hypothermia. He was expected to recover.