The US Coast Guard launched a search for 39 people reported missing when a boat capsized off the coast of Florida in a "suspected human smuggling venture," it said Tuesday.

The Coast Guard in Miami said it had received a report "from a good Samaritan" who rescued a man "clinging to a capsized vessel approximately 45 miles east of Fort Pierce Inlet."

The survivor said the boat had left Bimini in the Bahamas on Saturday night but encountered rough weather and capsized.

"According to the survivor, no one was wearing a life jacket," the statement said.

"Coast Guard air and surface asset crews are actively searching for people in the water. This is a suspected human smuggling venture," said the statement, which was posted on Twitter. 

An image released by the Coast Guard shows the capsized vessel in the water with a man straddling the hull.

Human smugglers are known to use the Bahamas, a group of islands lying near the Florida coast, as a jumping off point for getting people, many from other Caribbean countries such as Haiti, into the United States.

Bimini, the westernmost district of the Bahamas and its closest point to the mainland, is approximately 130 miles (217 kilometers) from Fort Pierce Inlet.

On Friday, 32 people were rescued after a boat capsized some five miles west of Bimini in another suspected human smuggling attempt, according to the US Coast Guard and the Royal Bahamas Defence Force. 

The US Coast Guard tweeted that its vessels patrol the waters around Haiti, Puerto Rico and the Bahamas "to ensure the safety of life at sea." 

"Navigating the seas in overloaded and less than seaworthy vessels is extremely dangerous and can result in loss of life," it warned.