DARTMOUTH, N.S. - A rare shipboard fire aboard a former coast guard vessel moored in Halifax harbour was brought under control Saturday after navy and city firefighters extinguished smouldering flames that had spread over several decks.

Nobody was aboard the 70-metre vessel, which was called the Sir Charles Tupper before it was sold to private interests and renamed the MV Caruso.

Firefighters said there were no injuries.

Dave Meldrum of the Halifax fire department said the blaze was difficult to bring under control and required the crucial services of the navy firefighting ship Firebird.

Standing before the burning ship, he looked on as crews advanced, cabin by cabin, through the listing vessel, pouring water on the smouldering remnants of the blaze.

"This is a tricky fire because it's a ship fire. We're a land-based municipal fire department. Our expertise is mostly with structures we find on land," he said.

"Ship fires have different characteristics. ... A big concern for us is how much water we can use before we actually hurt the ship's stability."

He said the assistance of the Firebird was central in battling the flames.

Firefighters initially went aboard the ship in the morning and hosed down the fire on the top deck.

But the fire spread to the lower decks, forcing crews to retreat.

Meldrum said firefighters were only able to return to fighting the blaze at close quarters early Saturday afternoon, after the heat and smoke died down.

The ship was stationed at a vacant mooring area on the Dartmouth waterfront and was scheduled to be refitted at a Halifax shipyard.

Keith Laidlaw, an environmental response officer with the Coast Guard, said there had been no fuel spills.

"There's been no releases and we don't expect there to be any," he said.

Meldrum said it's rare for the Halifax firefighters to have to deal with large shipboard blazes.

The highest-profile Nova Scotia ship fire in the past decade occurred in 2001, when the MV Kitano, a Japanese cargo vessel, caught fire while it was travelling between New York and Halifax.

In that fire, the Transportation Safety Board issued a 2003 report critical of the communication between the various firefighting forces involved, saying there was confusion over whether the navy firefighting vessel should be employed for the civilian blaze.

The Kitano was eventually tied to a wharf in the Bedford Basin, where its cargo containers were removed and Halifax municipal firefighters finished extinguishing the fire.

But Meldrum said the co-operation in Saturday's shipboard fire was exemplary, with the navy vessel playing a central role in containing the heat.