A 35-year-old man is in serious condition after a great white shark attack in California, authorities said.

       The incident occurred around 9:15 a.m. Saturday while the man was body boarding and skin diving, authorities said. The man was swimming off Grey Whale Cove State Beach in San Mateo County "when he was bitten in the right leg by a 6-8 ft. great white shark," according to the local sheriff's office.

       Cal Fire/Twitter

       Authorities said a man was bitten by a shark while swimming off a California beach on June 26, 2021.

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       The man was able to swim to shore, where he was treated by firefighters and paramedics "with advanced life support measures" before being transferred to a local trauma center, according to Cal Fire, one of several first responders at the scene.

       Cal Fire/Twitter

       The attack occurred at Gray Whale Cove State Beach in San Mateo County, authorities said.

       He had a confirmed bite and is in serious condition, Cal Fire said.

       A helicopter wasn't able to land because of the clouds so he was taken in an ambulance to Stanford Trauma Center with non-life-threatening injuries. He was later transferred to San Francisco General Hospital, authorities said.

       The beach is now closed. The state park is handling the investigation.

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       There were 33 unprovoked shark attacks on humans in the United States last year, three of which were fatal, according to data from the Florida Museum of Natural History at the University of Florida.

       Nearly half of the unprovoked attacks occurred in Florida. The fatalities were in California, Hawaii and Maine.

       ABC News' Alyssa Pone and Vera Drymon contributed to this report.