FEBRUARY 19, 2013 — In an e-mail to past guests, Carnival Cruise Line President and CEO Gerry Cahill said that "preliminary investigations indicate the cause of the [Carnival Triumph] fire was the result of a leak in the fuel return line for the number 6 diesel generator."

The investigation into the fire is being led by the Bahamas Maritime Administration with participation by the U.S. Coast Guard and the National Transportation Safety Board.

Media reports cite the Coast Guard as saying yesterday that the investigation of the fire will take six months. Although the source of the fire has been determined, pinpointing its exact cause will take longer.

The cruise shiip was in international waters at the time of the incident. It arrived in Mobile late Thursday under tow, after passengers and crew spent five days at sea without power or working toilets.

Interviews have been conducted with passengers and crew, and forensic analysis has been performed on the ship.  Investigators from the Coast Guard and NTSB will stay with the ship until the end of the week.

USCG Cmdr. Teresa Hatfield praised the actions of Triumph's crew in their response to the blaze, saying they had done a "very good job."

"We know that the fire originated in front of a generator," Patrick Cuty, a senior marine investigator for the U.S. Coast Guard, told CNN. "You can see the ignition marks on the wall."