A leaking fuel line was cited by Coast Guard officials as the likely cause of the engine-room fire that disabled the propulsion of the Carnival Triumph.
Fuel leaked from the return line of the No. 6 engine and ignited when it hit a hot surface, Lt. Commander Teresa Hatfield said in a telephone news briefing Monday.
According to published reports, Hatfield said the crew put out the fire "immediately" and it was contained to a small area.
Hatfield, who leads the Coast Guard's Marine Casualty Investigation Team in New Orleans, said firefighters "did a very good job."
The Bahamas is leading the investigation of the Carnival fire. The Triumph is registered in the Bahamas.
Hatfield said the Coast Guard expects to finish its onboard work by the end of the week and estimated the investigation would take at least six months. Follow Tom Stieghorst on Twitter @tstravelweekly.