Two migrant smuggling boats capsized in shallow but dangerous waters off the coast of San Diego, leaving at least 8 people dead.

That makes it one of the most deadly maritime human smuggling operations ever off the coast of the US.

On Saturday night, a Spanish-speaking woman on one of the boats called 911 to report that the other boat had overturned. She said there were 15 people on the vessel that went down, and 8 on hers.

The Coast Guard and San Diego Fire-Rescue crews were able to recover 8 bodies from the water, but fog made it impossible to be sure they found everyone.

They resumed searching on Sunday, but didn’t find any more bodies.

The whereabouts of the woman who called 911 are unknown, and it’s possible survivors escaped on land.