Workers look in the direction of the cruise ship Carnival Triumph in Mobile, Ala., Friday, Feb. 15, 2013. The ship, which Thursday docked in Mobile after drifting nearly powerless in the Gulf of Mexico for five days, was moved Friday from the cruise terminal to a repair facility. The ship carrying more than 4,200 passengers and crew members had been idled for nearly a week in the Gulf of Mexico following an engine room fire.

Associated Press Release

MOBILE, Ala. (AP) -- A Coast Guard official says the cause of the engine-room fire on the Carnival cruise ship Triumph was a leak in a fuel oil return line.

In a teleconference Monday, Cmdr. Teresa Hatfield estimated that the investigation of the disabled ship would take six months.

She said the Bahamas is leading the investigation, with the Coast Guard and National Transportation Safety Board leading U.S. interests in the probe.

She said investigators have been with the ship since it arrived Thursday in Mobile, and interviews have been conducted with passengers and crew.

The ship left Galveston, Texas, on Feb. 7 for a four-day trip to Mexico. The fire paralyzed the ship Feb. 10, leaving it adrift in the Gulf of Mexico until tugboats towed it to Mobile.