Late Friday night, a tragic incident unfolded off the coast of San Diego when a wooden boat, believed to be transporting migrants, overturned in treacherous waters, resulting in the deaths of four individuals and hospitalization of another four, according to authorities.

The US Coast Guard announced on Saturday its ongoing search efforts for any additional passengers who might have been aboard the panga-style boat when it capsized near Imperial Beach Drive around 11:40 p.m. local time, as detailed in an official press release.

This calamity coincided with a severe storm system that swept through Southern California, bringing intense rainfall and hazardous surf conditions. The adverse weather triggered warnings of flash floods and mudslides throughout the area.

Before the accident, Border Patrol agents in Imperial Beach had been tracking the small vessel as it journeyed from Mexican waters. They received alerts about its capsizing, which reportedly flung passengers into the Pacific Ocean, according to Imperial Beach Fire Chief John French in an interview with NBC San Diego.

Just minutes after the boat overturned, emergency teams discovered six individuals on the shoreline shortly before midnight, the Coast Guard reported.

One person was pronounced dead at the scene, while another was pulled from beneath the overturned boat and rescued.

Roughly two hours later, at 1:45 a.m. local time, a Good Samaritan reported seeing someone in the water near Imperial Beach Pier.

A Coast Guard boat crew from Station San Diego responded and recovered three people from the ocean. All three were pronounced dead after being transferred to Ballast Point, according to the Coast Guard’s official timeline.

One body was discovered floating near homes on Seacoast Drive and Encanto Avenue, NBC San Diego reported.

Emergency medical services transported four survivors to a nearby hospital for treatment, according to multiple outlets.

One person was taken into custody by Imperial Beach Border Patrol and later transferred to a Department of Homeland Security agency, the Coast Guard said.

Several of those aboard claimed Mexican nationality, while others remained unidentified Saturday, authorities said.

Reuters reported that Homeland Security Investigations has taken over the investigation of the incident.

“Our crews and partner agencies responded immediately, but this case demonstrates the severe risks posed to aliens attempting to enter the United States by sea in unstable vessels,” Coast Guard Capt. Robert Tucker, commander of the San Diego sector, said.

The vessel was a panga — a small, open fishing boat often used by smugglers to transport migrants from Mexico into California by sea, usually under cover of darkness and in perilous conditions, the Associated Press reported.

Migrants are increasingly relying on these risky sea routes as an alternative to heavily fortified land borders along California’s coast, according to the AP.

Pangas typically depart Mexico late at night and sometimes travel hundreds of miles north through open ocean.

In May, at least three people died when a panga flipped approximately 35 miles north of the US-Mexico border, the AP reported.

In 2023, eight people were killed when two migrant smuggling boats approached a San Diego beach in heavy fog and one capsized in the surf — one of the deadliest maritime smuggling incidents in US coastal waters.

A year prior, a federal judge sentenced a San Diego man to 18 years in prison after his overloaded boat carrying 32 migrants broke apart in heavy surf, leaving three dead and more than two dozen injured.