Three people are dead and at least seven more are missing after a small boat overturned in the Pacific Ocean off the coast near San Diego, California, officials said.

At least 16 people, including two children, were on board the panga-style fishing boat, which overturned near Torrey Pines State Beach, the US Coast Guard said in a statement on X. Initially nine people were reported missing but later two were found and detained.

A Coast Guard official told CBS News, the BBC’s US partner, that it is treating this as a suspected human smuggling incident.

Four people were taken to hospital, and it was unknown if any other victims were in the water, officials said.

It was unclear where the boat was coming from before it flipped about 35 miles (56km) north of the Mexico border, Coast Guard Petty Officer Chris Sappey told The Associated Press.

He said similar vessels are commonly used by smugglers. “They were not tourists,” Sappey said. “They are believed to be migrants.”

A panga boat is a small, open lightweight vessel typically powered by an outboard motor.

A Coast Guard cutter and a helicopter were searching for the missing, a Coast Guard spokesman told the BBC.

Nick Backouris, a lieutenant with the San Diego Sheriff’s office, said people from his office helped victims on the beach.

“A doctor hiking nearby called in and said, ‘I see people doing CPR on the beach, I’m running that way,'” Backouris told the AP. “The deputies were assisting with life-saving measures.”

Jorge Sanchez, of the Encinitas Fire Department, said the immigration status of those caught was not known.