Yacht Basin on Saturday, KPRC Local 2 reported.
At least seven people were injured in the explosion, including five on the boat and two
others nearby, the Coast Guard said.
The fire reportedly started shortly after 5 p.m. after the 40-foot craft was refueled.
A preliminary investigation indicated "there may have been some fumes that built up
below the deck," Coast Guard spokesman Gene Davis said.
"The vessel continued to burn, rolled over on its starboard side, and the lower hull separated
from the upper hull. Then, the vessel sank," Davis said. "The whole deck and everything
above it went."
Four victims were treated and released. Three others are being treated at Galveston's
The exact cause of the explosion is under investigation.