A decommissioned Russian nuclear submarine with 10 crew on board has sunk in the Barents Sea.
A spokesman for Russia's Northern Fleet said one of the crew had been rescued and the bodies of two others had been retrieved, the Interfax news agency reports.
Russia's Navy chief-of-staff Viktor Kravchenko told the NTV television channel that "the hopes of finding alive the missing are very slight".
He added that the vessel would be raised from the seabed "so it can be destroyed".
President Vladimir Putin - currently on a visit to Italy - has promised "a thorough investigation" into the incident.
The submarine's two nuclear reactors were shut down in 1989 and Russian officials said there were no weapons on board the vessel and no danger of nuclear contamination.
The incident comes three years after Russia's worst peacetime naval disaster when all 118 crew of the nuclear submarine Kursk died when it sank in the Barents Sea on 12 August 2000.
When the Kursk sank, Russia's Government and military were slow to admit what had happened, and slow to ask for foreign help searching for survivors.
This caused an avalanche of protests both in Russia and abroad, seriously denting the popularity of President Putin and the government.
The BBC's Damian Grammaticas says that this time at least the government has released information promptly and the Navy's chief-of-staff has already flown to the scene to oversee an investigation into the accident.
The submarine sank at 0400 local time (0200 GMT) about three miles off Kildin Island, in heavy seas.
K-159 NUCLEAR SUB
November class sub
Up to 86 crew
Can carry two nuclear reactors
Can be armed with low-yield nuclear torpedoes
Subs of this class entered service in late 1950s
Sources: Jane's Fighting Ships/Danish experts
The submarine - a November class K-159 - was on its way to be stripped of its nuclear reactors.
The Northern fleet's spokesman said the vessel was being towed on four floating hulls from its base in the town of Gremikha to a plant in the town of Polarnye to be scrapped.
He said the vessel became unstable after one of the hulls was torn off in a fierce storm and then sank in waters 170 metres deep.
Some experts have expressed doubts about the feasibility of salvaging the vessel.
"It is scrap metal and nothing more. It would keep us busy for no less than two years to lift a submarine from that depth," Russia's Rear Admiral Yuriy Senatskiy said.
"Moreover, a stormy season is coming. We have no resources for this kind of work. The Kursk has demonstrated that we are absolutely helpless in such matters," he added.
A Russian military prosecutor has opened an inquiry into the incident.
Since the collapse of the Soviet Union in 1991, Russia has decommissioned about 190 nuclear powered submarines.
But experts say more than half of them still have nuclear fuel in their reactors.
While there are concerns that the nuclear materials could be stolen for extremist groups or other nations, experts say the bigger threat is thought to be the possibility of an accident.
The submarines spend years sitting in berths, their hulls rusting, often getting inadequate maintenance.
The Russian Government cannot afford to keep them, but it also cannot afford to dispose of them safely, without international assistance.
Russian officials estimate it will cost nearly $4 billion to scrap all the vessels - but last year the government budgeted just $70m for improving nuclear safety in the country as a whole.