The Russian Navy has concluded the final sea trials for the Akula II Class submarine K-152 Nerpa, which was damaged in a fatal accident during tests in November 2008.

Khabarovsk Territory governor Vyacheslav Shport was quoted by Ria Novosti as saying the submarine is in a good state of readiness and will be commissioned on time.

Following the $60m repair work, the submarine was cleared for final sea trials before being commissioned with the Russian Navy, and will be leased to the Indian Navy in 2009 as the recommissioned INS Chakra.

The 12,000t K-152 Nerpa is considered the quietest and deadliest of all Russian nuclear-powered attack submarines.

During an underwater test run in the Pacific Ocean on 8 November 2008 the on-board fire suppression system of the submarine activated, releasing deadly gas into the sleeping quarters. At least 20 people were killed in the accident. 208 people were on board at the time, 81 of them submariners.

The vessel resumed sea trials on 10 July 2009 in the Sea of Japan. Reports say that the Indian Navy paid $650m for a ten-year lease of the Akula II Class nuclear-powered attack submarines.