A shark has attacked a woman in the waters off San Diego.
The woman was treated in hospital for puncture and laceration wounds to her upper right thigh, according to Jon Edelbrock, lifeguard chief for the city of Del Mar.
The woman has received stitches and is recovering.
Mr Edelbrock said the shark may have been a juvenile great white shark, though officials are waiting for scientists to confirm that.
Juvenile great white sharks often swim in the Pacific waters off Del Mar’s shoreline.
A lifeguard spotted the woman with a friend just after 10am on Friday as they were heading back to shore after swimming more than a mile, Mr Edelbrock said.
He noticed their strokes changed and the friend waving his arms for help when they were a few hundred metres from the beach, but outside of the surf zone.
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He said lifeguards helped the pair back to shore, but did not spot the shark.
The beach has been closed for at least 48 hours.
“She had a diligent swim buddy,” Mr Edelbrock said. “They both maintained their composure quite well.”
Del Mar sits around 20 miles (32km) north of downtown San Diego.
An 8ft-long juvenile great white shark washed up dead on Sunday on the shores of Torrey Pines State Natural Reserve and State Beach, nearly three miles south of the attack on Friday, according to local media reports.