Ceremonies are being held in Russia and on board its naval vessels to commemorate the 10th anniversary of the Kursk nuclear submarine disaster.

The submarine, one of the Russian navy's most advanced vessels, sank in the Barents Sea on 12 August, 2000 with the loss of all 118 people on board.

An explosion of fuel from an old torpedo caused the disaster.

Moscow's response to one of the greatest disasters in Russian naval history was widely criticised.

Relatives and members of Russia's northern fleet are due to cast wreaths into the sea on Thursday in memory of the crew.

Flags are being flown at half-mast at the headquarters of all Russia's naval fleets, and a ceremony and minute's silence was being held at Moscow's Central Army Museum.

Delayed response

The initial response to the disaster in 2000 was shambolic, says the BBC's Richard Galpin.

After radio contact was lost there was a still unexplained delay before a search and rescue mission was launched.

Although the submarine was lying just 100m below the surface of the sea, attempts to locate it and reach it repeatedly failed....