At least three people died and seven others, including two children, were missing after a small boat capsized in choppy seas off the California coast in a suspected migrant smuggling attempt north of San Diego, US officials said on Monday.

Four survivors rescued after the “panga”-style open fishing vessel washed ashore near Torrey Pines State Beach were transported to hospitals, and two other people found on a nearby beach were detained by authorities, according to US Coast Guard officials.

The two taken into custody were suspected to be smugglers, Coast Guard spokesperson Hunter Schnabel told Reuters.

Earlier Coast Guard accounts put the number of people missing from the overturned craft at nine, but Schnabel said the tally of those unaccounted for was revised to seven after confirmation that two individuals had been detained.

A Coast Guard cutter, an emergency response boat and a helicopter were involved in an ongoing search for the missing, among whom were two children, another Coast Guard spokesperson, Chief Petty Officer Levi Read, said.

At least some of the boat’s occupants were apparently from India, as a number of Indian passports “were found on the beach near where the panga washed up,” Read said.

Shawn Gibson, a special agent in charge of the US Homeland Security Investigations (HSI) agency, said the incident was a “stark reminder of the dangers posed by maritime smuggling.”

“The ruthless smuggling of undocumented individuals is not only illegal, it’s deadly,” Gibson said of the incident, which occurred about 30 miles north of the US-Mexico border. Read said ocean conditions off the San Diego County coast were rough at the time, with two metres seas reported.

Personnel from HSI, the US Border Patrol, the local fire department and law enforcement also responded to the scene, officials said.

So far this fiscal year, since October 2024, the Coast Guard has tracked 277 vessels clandestinely entering US waters from Mexico in the San Diego area, some of the boats being interdicted and others getting away, Read said. Those incidents resulted in 983 people being apprehended.

That compares with 1,354 maritime border-crossing incidents in the same region during the previous 12 months, with 561 individuals taken into custody during that period.

Of the four hospitalised survivors from Thursday’s panga capsizing, one was listed in critical condition when rescued, according to a statement from the city of Encinitas.

One survivor reported that 18 people had been aboard the vessel, and 18 life vests were located on shore, the statement said. But Read said the Coast Guard’s best information was that the boat was carrying just 16 individuals when it capsized.