Nerpa (renamed INS Chakra in Indian Navy service) is a 8,140-tonne (8,010-long-ton) Project 971 (or Project 518; NATO: Akula-class) nuclear-powered attack submarine. The construction of the submarine was started in Russia in 1993, but was suspended due to lack of funding. India then sponsored further construction and sea trials of the submarine provided it was leased to the Indian Navy for 10 years. It was launched as K-152 Nerpa in October 2008 and entered service with the Russian Navy in late 2009. The submarine was leased to the Indian Navy in 2011 after extensive trials, and was formally commissioned into service as INS Chakra with the Eastern Naval Command at a ceremony in Visakhapatnam on 4 April 2012. In June 2021 Chakra was spotted on the surface escorted by Indian and Russian wars