(CNN) -- Crew members and military personnel onboard a Danish cargo ship that caught fire off the coast of Norway are trapped on the vessel after a rescue attempt Saturday was halted because of bad weather, authorities said.
A helicopter airlift to rescue some the the Britannia Seaways was halted because of strong winds, said John Sjurso, a spokesman for the Joint Rescue Coordination Center of Southern Norway.
The fire began Saturday in a container on the ship's upper deck, and Saturday night rescue officials said there is a second fire burning in a lower deck.
The Britannia Seaways was in the North Sea en route from northern Norway to Bergen, Sjurso said. The cause of the fire was not immediately known.
According to a rescue agency spokesperson there are 20 crew members and 12 military personnel aboard the Britannia Seaways.
Crew members were fighting the fire, but it was not immediately known what equipment they had at their disposal to battle the flames, rescue officials said.
There were no immediate reports of injuries.
The Britannia Seaways, a three-deck cargo ship, is carrying 24,000 tons of military equipment.
Officials added late Saturday that the ship is still running under its own power.