A nuclear attack submarine involved in a fatal accident during sea trials last year will be commissioned by the Russian Navy in the fall and then leased to the Indian Navy, a source said on Tuesday.
The Nerpa nuclear-powered submarine was undergoing sea trials in the Sea of Japan on November 8 last year when its on-board fire safety system went off, releasing deadly gas into the sleeping quarters. Three submariners and 17 shipyard workers were killed. There were 208 people, 81 of them submariners, on board the vessel at the time.
"Following new official state sea trials in the summer, the sub will be put in service with the Navy in the fall of this year," the Russian naval source said.
He added that the Nerpa would be leased to the Indian Navy shortly after the commissioning, and said India had paid over $500 million for a 10-year lease of the 12,000-ton nuclear attack submarine.
Indian media have reported that the construction of the vessel was partially financed by the country's government.
The construction of the Akula II class Nerpa nuclear attack submarine started in 1991, but was suspended for over a decade due to a lack of funding.
Akula II class vessels are considered the quietest and deadliest of all Russian nuclear-powered attack submarines.
India is one of the main buyers of Russian weaponry, with contracts including the delivery of Admiral Gorshkov aircraft carrier with at least 16 MiG-29K Fulcrum-D carrier fighters, the Smerch MLRS, and licensed production of T-90 tanks in India.
Russia signed in March last year a contract with the Indian Defense Ministry to upgrade around 70 MiG-29 fighters, in service since the 1980s, and agreed to develop a fifth-generation fighter together with India.
Russia and India jointly developed the BrahMos supersonic cruise missile, whose sea-based and land-based versions have been successfully tested and put into service with the Indian army and navy.