
Project 877EKM is an export version of Kilo-class submarines. A total of 18 subs have been delivered to Iran, China, India, Poland, Romania and Algeria. INS Sindhurakshak, an Indian Navy Project 877EKM sub that was handed back to India in January 2013 after a major refit at Russia's Zvezdochka shipyard, sank in the port of Mumbai on August 14 following a fire and a series of explosions on board.