Russian sub crew 'alive'

Over 100 crew members are on board on the Kursk

The crew of the stranded submarine Kursk are alive, according to a Russian navy spokesman.

Mini-submarines and a diving bell have been able to get near the stricken sub and rescue teams have been communicating by tapping on the hull of the vessel.

But Russia's navy chief, Admiral Vladimir Kuroyedov, has warned that the sailors chances of survival are "quite low".

The Kursk, one of the most modern submarines in the Russian fleet, is spending its third day at the bottom of the Barents Sea after suffering damage and running aground during exercises at the weekend.

"The prognosis... for the Kursk and for the lives of the crew appears extremely grave," Admiral Kuroyedov was quoted as saying by the navy press office.

Officials said it had been established that all 116 crew were "alive for the moment".

However, asked by the Interfax news agency whether there had been casualties, Admiral Kuroyedov said he did not know.

Bad weather has added to the problems at the scene, with choppy seas and high winds reported to have worsened overnight on Monday.

Explosion theory

The Oscar-II class nuclear submarine, was damaged during naval exercises on Saturday or Sunday and sank to the seabed off the naval base of Severomorsk, near Murmansk.

Kursk facts

Launched May 1994

Length 155 metres

Displaces 18,300 tonnes

Armed with guided missiles and torpedoes

Designed to strike against surface forces especially aircraft carriers

Source: Jane's Fighting Ships

Russian media have speculated about the possibility of a collision with a foreign submarine, but Admiral Kuroyedov said on Tuesday that the most likely explanation was an explosion in a torpedo compartment.

US officials have said that two of their submarines and a surface vessel were in the area, but that none of them had been involved in a collision.

One of the US submarines reported having heard an explosion at the site on Saturday, however it is unclear whether this was the sound of an incident on the Kursk, or just one of the many bombs and shells used in the exercises.

Russian officials say they have confirmed that the front of the submarine is badly damaged.

Oxygen

Latest reports suggest that efforts to supply the vessel with oxygen and power were unsuccessful.

A decision on how to mount a rescue operation is expected some time on Tuesday.

The United States, France and the UK have offered to assist in the operation, but Russian naval authorities say they have all the facilities they need.

Navy officials said the submarine was not carrying any nuclear weapons, and no radiation leaks have been reported.

According to an official of Russia's Northern Fleet, the vessel is lying at a depth of about 102 metres, approximately 135km (85 miles) off Severomorsk.

The craft was reported to be listing at about 60 degrees to starboard.

In 1989 42 Soviet sailors died when another submarine, the Komsomolets, sank in the Barents Sea

Russian navy press officer Igor Dygalo said both the submarine's nuclear reactors have been shut down.

The BBC's defence correspondent, Jonathan Marcus, says if the submarine had power and the damaged compartments had been sealed off, the submarine could remain quite safely on the bottom for a lengthy period of time.

However, without power or with merely auxiliary batteries the situation could be very different.

Russian sources say the fact that the submarine is not in radio contact could mean that its batteries are not working - or that it set to sea without any.

Defence analyst Paul Beaver of Jane's Defence Weekly said on Monday the crew could have less than 48 hours before the air supply runs out.