US Coast Guard officials are searching for 39 people who are feared missing after their ship reportedly capsized on Saturday night off the Florida coast.
Officials were alerted on Tuesday morning after fishermen spotted a man clinging to the hull of a boat 45 miles (72km) from the city of Fort Pierce.
The survivor said the group had embarked from Bimini, Bahamas, on Saturday night and hit foul weather.
US officials say the boat may have been part of a "human smuggling venture".
According to the survivor, who has not been identified, none of the passengers were wearing life vests.
The search was being led by the Miami Coast Guard sector using ships and aircrafts, the agency said on Twitter.
By Tuesday afternoon, no further survivors had been found.
The island of Bimini is the western-most district of the Bahamas, and is only 80 miles from Miami.
Officials are searching from Bimini to Fort Pierce, an area roughly 135 miles wide.
On Friday, the Coast Guard reported that they had found 88 Haitians in an overloaded ship west of the Bahamas.
"Navigating the Florida Straits, Windward and Mona Passages in overloaded and less than seaworthy passages is extremely dangerous and can result in loss of life," the Coast Guard said in a statement.
"The Coast Guard and our partner agencies will continue to stop these voyages. You will be interdicted and should expect to be returned and repatriated to your country of origin."