Four people were rescued from a flame boat on Saturday off the coast of Cabo Cañaveral, Florida.
A good Samaritan helped rescue some of the unidentified passengers, said the United States Coast Guard.
The black smoke was undulating in the air while beach lovers and other people watched from afar.
There were no reported injuries and the cause of the fire was still under investigation until Saturday night, the Coast Guard said.

This screenshot of a video filmed by observer Tami Winston from a hotel in Cape Canaveral, Florida, shows that the smoke rises in the air from a fire in a boat.
Tami Winston