The hull is buckled, the hatch is blocked

Stricken submarine: A remote-controlled camera reveals the extent of the damage to the 'Kursk', and the problems ahead

The first remote-controlled camera sent down to the Kursk from the Norwegian ship Seaway Eagle at 7am yesterday morning revealed the extent of the problems facing the divers and the British mini-submarine LR5. The film shows a crack along the rim of the escape hatch close to the stern, suggesting an explosion buckled the Kursk's entire 490ft hull.

The first remote-controlled camera sent down to the Kursk from the Norwegian ship Seaway Eagle at 7am yesterday morning revealed the extent of the problems facing the divers and the British mini-submarine LR5. The film shows a crack along the rim of the escape hatch close to the stern, suggesting an explosion buckled the Kursk's entire 490ft hull.

"This inspection showed a serious crack," said the Russian Deputy Prime Minister, Ilya Klebanov. "That is why we think the British sub will not be able to dock, and our main hope is on the manual work, together with a [diving] bell of the Norwegian divers."

Mr Klebanov said the first five or six compartments of the submarine had been flooded on 12 August, when an explosion ripped through the bow section, leaving only the sailors in the three stern compartments a chance to survive.

The first three Norwegian divers, in a team of 12 working in relays, entered the water an hour after the remote camera was sent down. The others waited in a compression chamber on the surface adapting to the pressure on the sea-bed.

Russian television claimed the divers had found a bodytrapped in the submarine's airlock leading out of the vessel. The divers were able to open the outer cover of the escape hatch but the body may be blocking the way in.

The Norwegians also tapped the hull of the Kursk and believe they found some air pockets. Russian officials said the water was also checked for radiation from the Kursk's two reactors. These should have shut down automatically when disaster struck, even if most of her crew was already dead.

The divers work slowly in diving suits that look like space suits, heated by warm water circulating to protect them from icy Arctic seas. The bulky suits may make it difficult to enter the narrow escape hatch.

Arkady Mamantov, of Russia's RTR television, the only correspondent on the scene, said the divers had used heavy tools to open the bolts on the hatch. He also said that although the sky was still clear, the weather was expected to worsen, increasing the difficulties of the rescuers.

If the compartment below the escape hatch is already filled with water, there will be no opportunity for the LR5, waiting six or seven miles from the Seaway Eagle, to use its so-called "transfer skirt". This is a pressure-resistant tube which would be placed over the hatch and water pumped out to establish an escape route.

The last terrible moments of the Kursk had already been graphically described by Vice-Admiral Mikhail Motsak, chief of staff of the Northern Fleet. He said the Kursk had been at periscope depth when an explosion or a collision had sent it plunging into the sea-bed. The crash had detonated a torpedo, ripped a three-foot hole in the hull and probably ruptured the high-pressure air pipes.

Most of the crew probably died immediately in the forward section of the Kursk which also contains the control room.

But in the rear compartments, several sailors survived at least until last Tuesday - more than 48 hours after the submarine sank - when tapping was heard.

Admiral Motsak said: "The crew in the compartments in the stern were telling us that the water was filtering into their sections and they wanted us to provide air supply." He said the rescuers were unable to do this, adding: "That's a possible construction defect, on which we'll have to work in future submarines."

The incoming seawater would have compressed the air. "As water slowly filled the compartments in the stern the pressure inside built up, inevitably reducing the life expectancy of the crew."

At this point, the rear escape hatch would have been the only possible exit point on the submarine since the forward escape hatch and large escape pod on the sail, or conning tower, would have damaged.

The Russian Navy now believes the disaster which destroyed the Kursk was the result of a powerful internal explosion. It says this happened after it hit the sea floor.

At issue is the reason why it took its final dive. Admiral Motsak says it may have hit a Second World War mine. Six have been discovered in that area of the Barents Sea between 1992 and 1999.

The Kursk was also using liquid-fuelled torpedoes which are regarded as dangerously unstable, although they provide greater range and impact.

One explanation is that the two explosions heard by seismic stations in just more than two minutes were from the fuel of a torpedo exploding, followed by its warhead.

Even, as seems most probable, the Kursk is now only a metal coffin filled with seawater - save for a few air pockets - the rescuers will want to bring up the bodies.

The Russian Navy says it wants to raise the submarineto remove its nuclear reactors and its weapons as well as identify the cause of its last, fatal dive.