Kursk submarine disaster
The nuclear-powered Project 949A "Antey" (Oscar II class) submarine "Kursk" (Russian: ) sank in an accident on 12 August 2000 in the Barents Sea, during the first major Russian naval exercise in more than ten years, and all 118 personnel on board were killed. The crews of nearby ships felt the 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 sub for more than six hours. Because the submarine's emergency rescue buoy had been intentionally disabled during an earlier mission, it took more than 16 hours to locate the sunken boat. 