The Russian Navy’s ill-fated Nerpa nuclear attack submarine has been officially commissioned, following successful final sea trials in the town of Bolshoy Kamen in the Russian Far East.

The Akula II class nuclear submarine, which is destined for the Indian Navy, underwent repairs worth $65m and successfully cleared the final sea trials which proved the submarine’s operational readiness, according to RIA Novosti.

The submarine suffered setbacks during sea trials in November 2008 after a fatal gas leak cost the lives of 20 crew members.

The 12,000t K-152 Nerpa nuclear submarine will be renamed INS Chakra for the Indian Navy.

Of all the Russian nuclear-powered attack submarines, Akula II class submarines are considered the quietest and most powerful weapons in the naval fleet.