ISLETON (CBS/AP) — Authorities are searching for a 41-year-old Stockton man who jumped into a swift-moving river in the San Joaquin Delta after his 1-year-old son fell out of their fishing boat.

Sacramento County Sheriff’s Sgt. Shaun Hampton said the man’s 10-year-old daughter called 911 on Friday and said her father had jumped in the San Joaquin River at Isleton without a life vest to rescue her brother.

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Hampton said a U.S. Coast Guard crew located the boat and the boy floating in the frigid, murky water. He initially didn’t have a pulse and was taken to a Sacramento-area hospital where Hampton said his conditions improved as of Saturday.

Two other children who were on the boat were reunited with family.

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Hampton said the water has been moving fast due to heavy rainfall and runoff.

The incident happened near Pirate’s Lair Marina, south of Isleton.

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