Seven crew sent to hospital while others remained on the Yekaterinburg in Arctic shipyard during blaze

A massive fire was put out on a docked Russian nuclear submarine outside the north-western city of Murmansk as some crew members remained inside, officials said.

Military prosecutors have launched an investigation into whether safety regulations were breached, and the Russian president, Dmitry Medvedev, summoned top cabinet officials to report on the situation and demanded punishment for those responsible.

The fire broke out on Thursday at an Arctic shipyard where the submarine Yekaterinburg was in dry dock. Firefighters continued to spray the vessel with water to cool it down.

Russian state television earlier showed the rubber-coated hull of the submarine still smoldering, with firefighters standing on top to douse it with water.

Seven members of the submarine crew were taken to hospital after inhaling carbon monoxide fumes.

An unspecified number of crew remained inside the submarine during the fire, a defence ministry spokesman said in a statement. He insisted there never was any danger of the fire spreading inside the sub and said the crew reported that the conditions on board remained normal.

The statement left it unclear whether the crew were trapped there or ordered to stay inside.

The Russian defence and foreign ministries said there had been no radiation leak and Norway's Radiation Protection Authority reported it has not measured any increased radioactivity.

But the governor in Finnmark, Norway's north-eastern province bordering Murmansk region in Russia, told Norwegian broadcaster NRK that he was disappointed with Russia's response.

"There have been problems to get clear information," Gunnar Kjoennoey said. "We have an agreement to exchange information in such cases, but there has been no information from the Russian side so far."

Russia's military says the blaze started on wooden scaffolding and engulfed the sub's outer hull. Its nuclear reactor had been shut down and its nuclear-tipped missiles and other weapons had been unloaded before the repairs, it said.

The Yekaterinburg is a Delta-IV-class nuclear-powered submarine that normally carries 16 nuclear-tipped intercontinental ballistic missiles. It was commissioned in 1985.

The Russian navy suffered its worst accident in August 2000, when the Kursk nuclear submarine exploded and sank, killing all 118 crew members aboard.

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