The U.S. Coast Guard suspended its search for an estimated 11 additional people who went missing approximately 140 miles off Baja California, the agency announced Sunday.

On Oct. 16 at approximately 1 a.m. the Coast Guard assisted Mexican authorities in a search-and-rescue operation off the coast of Ensenada, Mexico, after receiving a distress call from a vessel whose occupants said it was sinking.

That morning, 16 people were rescued and transferred to hospitals in San Diego for medical care.

Preliminary information stated 27 people needed rescuing, but the Coast Guard later said they do not have a total number of people confirmed.

The search spanned more than 2,441 square miles and lasted a combined 89 hours.

“Suspending a search is never easy, and this was an exceptionally dynamic case, far offshore, in rough weather. We can say with confidence that human traffickers have zero regard for human life and routinely put the lives of illegal aliens and the lives of rescue crews at risk,” said Capt. Joseph Meuse, chief of staff for the Coast Guard Southwest District.

On Friday, the Coast Guard said it had not confirmed whether the vessel was involved in a human smuggling operation. U.S. Customs and Border Protection said its officers were not currently involved in the response.

On Sunday, the Coast Guard added that the incident is under federal investigation.