A sailor serving on the Russian nuclear submarine Nerpa has been charged with "criminally negligent homicide" in connection with the deaths of 20 people aboard the vessel earlier this month, local media reported Monday.

The contract sailor, Dmitry Grobov, faces a sentence of up to five years in prison if convicted, Alexander Bastrykin, head of the Investigative Committee, was quoted by RIA Novosti and Itar-Tass as saying.

The deaths of three naval officers and 17 members of a shipyard crew occurred Nov. 8 when the fire extinguishing system of the submarine, which was on sea trials in the Sea of Japan, launched unexpectedly and released freon gas into the air.

Investigators said Grobov activated the system without permission and has already confessed.

The last major tragedy on a Russian nuclear submarine occurred Aug. 12, 2000, when the Kursk sank during a military exercise in the Barents Sea after an explosion ripped through the vessel. All 118 sailors perished.

(Xinhua News Agency November 24, 2008)