No hope of finding anyone alive as four bodies are discovered aboard sunken Indian submarine

Indian navy divers at the site of the stricken INS Sindhurakshak (Getty Images)

Indian navy divers have recovered the bodies of four sailors who were trapped inside a submarine damaged by twin explosions, a navy spokesman confirmed.

Narendra Vispute confirmed they were not expecting any of the other 14 sailors on board to have survived.

He said the bodies are so badly burned that they will need to be identified using DNA tests.

The bodies are severely disfigured and not identifiable due to severe burns," he said.

"However, the navy will continue to search every inch of the submarine until no bodies remain to be found."

He told reporters that the condition of the bodies suggested all 18 crew members were killed in the blasts in the vessel's home port of Mumbai.

The 16-year-old diesel-powered, Russian-made submarine, INS Sindhurakshak, was rocked by two explosions in the torpedo compartment that sent huge fireballs into the air.

The vessel was left partially submerged at Mumbai's naval dock, with just a portion left visible above the waterline.

The submarine recently returned from Russia after a two-and-a-half-year refit, overhaul and upgrade and had been certified for use by the Indian navy.

Russian ship repair company Zvyozdochka said the blasts were unrelated to its repair work.

Reaching sailors trapped in the ruined, water-filled vessel was made all the more difficult because the heat of the blast melted some hatch doors shut. The navy said there has been no contact or movement from any of the sailors since the accident occurred.

The same submarine was hit by an explosion in 2010, killing one sailor and injuring two others. The navy said that accident was caused by a faulty battery valve which leaked hydrogen, causing an explosion in the vessel's battery compartment. There have been no details on the cause of this week's blasts.

Additional reporting by Associated Press