A San Francisco State University student is missing after participating in a "polar plunge" event off the California coast.
Hamzah Alsaudi, 22, was reportedly hit by a large wave during the swimming event at Esplanade Beach. The incident occurred around 10.30am on Thursday, according to Pacifica police.
The strong waves pulled the college sophomore away from the beach, after which he disappeared beneath the waves. His friends, who had been swimming with him at the time, ran to the beach and called 911, The New York Post reports.
Authorities rushed to the area to search for Mr Alsaudi using aircraft, a boat, and the combined efforts of police, the Coast Guard, and lifeguards, but could not locate the college student.
The university announced in a statement that the search for Mr Alsaudi will not be resumed.
"I write to you with a heavy heart," the school wrote in the statement. "At this time, we have been told that authorities are no longer actively searching for Hamzah, and he is considered missing."
The waters near Pacifica, which is approximately 15 miles south of San Francisco, were experiencing dangerous riptides on the day Mr Alsaudi leapt into the water, according to authorities.
Mr Alsaudi’s friends told KTVU they were participating in a polar plunge event when the incident occurred. Polar plunges are challenges that involve swimmers leaping into exceptionally cold water.
Callum Bisping, one of Mr Alsaudi’s friends and teammates on the university’s wrestling team, told the broadcaster that his friend’s disappearance has not fully hit him yet.
"Sad, obviously. It hasn’t fully set in yet. He was an amazing guy, one of my best friends on the team," he said. "Very giving."
A local resident, Diana Compin, told KTVU she was out walking when she stumbled onto the scene just after Mr Alsaudi was pulled out to sea. She found his friends and said they appeared distraught, noting they were "shaking so bad because of what was going on, not because it was cold."
"This poor kid was just not together," she said.