The Russian Navy submarine Kursk explodes and sinks in the Barents Sea during a military exercise, killing her entire 118-man crew.

The Russian Navy is the naval arm of the Russian Armed Forces. It has existed in various forms since 1696. Its present iteration was formed in January 1992 when it succeeded the Navy of the Commonwealth of Independent States.

K-141 Kursk was an Oscar II-class nuclear-powered cruise missile submarine of the Russian Navy. On 12 August 2000, K-141 Kursk was lost when it sank in the Barents Sea, killing all 118 personnel on board.

The Russian nuclear submarine K-141 Kursk sank in an accident on 12 August 2000 in the Barents Sea, with the loss of all 118 personnel on board. The submarine, which was of the Project 949A-class, was taking part in the first major Russian naval exercise in more than 10 years. The crews of nearby ships felt an initial explosion and a second, much larger explosion, but the Russian Navy did not realise that an accident had occurred and did not initiate a search for the vessel for over six hours. The submarine's emergency rescue buoy had been intentionally disabled during an earlier mission and it took more than 16 hours to locate the submarine, which rested on the ocean floor at a depth of 108 metres (354 ft).

The Barents Sea is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territorial waters. It was known earlier among Russians as the Northern Sea, Pomorsky Sea or Murman Sea ; the current name of the sea is after the historical Dutch navigator Willem Barentsz.