Kursk investigators prepare to board sub

The wreck could barely be seen until it reached dry dock

A team of investigators led by the Russian Prosecutor General, Vladimir Ustinov, is preparing to enter the wreck of the Kursk submarine for the first time.

Mr Ustinov's team will scour the vessel for clues to the causes of the disaster, which claimed the lives all 118 men on board in August of last year.

Without examining the bow of the boat, it is impossible to completely clarify the cause of the disaster

Russian Prosecutor General Vladimir Ustinov

The green light for the investigation was given after the wreck was detached from a giant barge which had towed it into dry dock in the Arctic port of Roslyakovo after it was lifted from the bed of the Barents Sea earlier this month.

But much work remains to be done to ensure the safety of the missile-carrying submarine and its nuclear reactors, and the investigation may eventually focus on the bow of the Kursk - still to be removed from the seabed.

Search for evidence

"Without examining the bow of the boat, it is impossible to completely clarify the cause of the disaster," Mr Ustinov said before leaving Moscow.

The bow had been cut from the main part of the Kursk because of the danger posed by the torpedoes. Some experts believe that the explosions which destroyed the submarine probably originated there.

The wreck was dragged into dock by a giant barge

The Russian authorities have said they will try to recover the bow next year. But Vice-Admiral Mikhail Barskov, the officer charged with the recovery of the Kursk, has already said it is in such a poor condition it cannot be lifted as a whole.

When Mr Ustinov's team enters the Kursk, the new evidence it will look for will include journals and notes by officers and men.

The prosecutor general has warned that if any senior naval officers are found guilty of causing the loss of the Kursk, they will "bear responsibility regardless of their years of service".

Recovery work continues

Theories for the disaster include the explosion of a faulty torpedo in the bow and a collision with another submarine or old anti-shipping mine.

Workers could step onto the wrecked submarine between the pontoons

One contentious theory, carried by some Russian and German media, is that the submarine was hit by a missile fired in error by a Russian warship during exercises.

Vice-Admiral Barskov has warned that the dangerous task of dismantling the Kursk's 22 Granit cruise missiles is still ahead.

He spoke of "a significant element of risk" but ruled out the possibility that they could launch by themselves.

Another threat is posed by the Kursk's two nuclear reactors but Russian radiation tests conducted to date do not show hazardous levels.