MOSCOW, Feb 13: A fire at a dry-docked Russian nuclear submarine in December could have sparked a radiation disaster because it was carrying nuclear-tipped ballistic missiles and other weapons, despite official statements to the contrary, a Russian news magazine reported Monday.

When the fire erupted on Dec 29, Russia's Defence Ministry said all weapons had been unloaded before the submarine was moved to a dry-dock for repairs at the Roslyakovo shipyard in the Murmansk region. The ministry declined immediate comment on the magazine's claim.

It took hundreds of emergency workers more than 20 hours to extinguish the massive blaze that shot orange flames up to 66 feet into the air. The Defence Ministry said an unspecified number of crew members remained inside the sub during the fire and that seven crewmen were hospitalised after inhaling carbon monoxide fumes from the blaze.

The fire, which authorities later blamed on a breach in safety regulations, erupted at wooden scaffolding around the sub and quickly engulfed the vessel's rubber-coated outer hull.

With the sub's hydraulic systems incapacitated, the crew had to manually remove heavy torpedoes from tubes in the bow to prevent them from exploding as temperatures were rising quickly.

The magazine said that an explosion of torpedoes, each carrying 660 pounds of TNT would likely have destroyed the bow and could have triggered a blast of nuclear-tipped missiles in the midsection and the vessel's two nuclear reactors.

“Russia was a step away from the largest catastrophe since Chernobyl,” Komersant Vlast said, referring to the 1986 explosion at a nuclear power plant in then-Soviet Ukraine.

The magazine said that weapons are normally removed from submarines before repairs, but the navy wanted to save time on a lengthy procedure to unload the missiles and torpedoes. It said the repairs were supposed to be relatively minor and the Northern Fleet wanted the Yekaterinburg to be quickly back to service.—AP