The Kursk disaster was caused by one of the submarine's torpedoes exploding, according to the man in charge of the investigation into the accident.

All 118 crew members died in the catastrophe in August last year on board one of Russia's most advanced submarines.

Russian Deputy Prime Minister Ilya Klebanov told Russian TV: "What is absolutely clear is that the destruction we spoke about during the past year...was caused by the initial explosion of one of the torpedoes."

But Mr Klebanov said the investigators had yet to establish what had led to the torpedo explosion.

He offered three possible explanations - a fault with the torpedo, collision with a mine, or another kind of collision.

Missiles removed

Earlier on Monday, the Russian salvage workers removed the first three of 22 Granit cruise missiles from the submarine.

"The operation followed normal procedure, just as it would with any other submarine," an official of the Northern Fleet told the AFP news agency.

What is now absolutely clear is that the destruction we spoke about... was caused by the initial explosion of one of the torpedoes

Ilya Klebanov Russian Deputy Prime Minister

Experts expressed fears, as the submarine was being lifted from the sea bed, that any sharp movement could cause a damaged missile to explode.

Russian officials have always denied that the missiles are carrying nuclear warheads.

Explosions hell

So far 45 bodies have been removed from the submarine since it was lifted into dry dock last week.

Of these 25 have been identified, and seven have been flown out to relatives.

Click here to see a graphic of the inside of the Kursk

Another 12 bodies were removed last year.

Investigators have been working round the clock in shifts.

The bow of the Kursk is still on the seabed

"People are hellishly tired, but nothing can make them leave the wreck," said Leonid Troshin, spokesman for prosecutor general Vladimir Ustinov.

Mr Ustinov described on Saturday the "hell" that followed the explosions as fire swept through the submarine.

The flames would have been quenched by the icy water that flooded the Kursk within seven to eight hours, but any attempt to rescue crew members who fled to the rear of the boat would have been futile, he said.

Missile questions

Mr Troshin said the search for bodies was now focused on the middle of the vessel, as there were none left in the three sections closest to the stern.

People are hellishly tired, but nothing can make them leave the wreck

Leonid Troshin Spokesman for Prosecutor General

Mr Troshin said work was stopped briefly on Monday because some compartments had to be cleared of high concentrations of lethal hydrogen sulfite.

Investigators also could not reach a section connecting the two compartments containing the submarine's two nuclear reactors as it was filled with debris from the blasts, he said.

Nuclear warheads

Russian defence analyst Pavel Felgenhauer has questioned the official line that there were no nuclear warheads on board the Kursk.

He points out that immediately after the Barents Sea exercises, the submarine had been due to leave for the Mediterranean on an expedition for which it would certainly have been armed with nuclear missiles.

Investigators believe the wreck will provide many clues to the cause of the blasts, but say a definitive answer may only become possible when the bow section is raised.

It was sawn off and left on the seabed and is due to be raised next year.

Click here to return