NEW DELHI (AP) -- Eighteen sailors were trapped aboard a submarine that caught fire and sank Wednesday morning after an explosion, an Indian navy official said. He said other sailors were working frantically to save them.
The diesel-powered submarine sank at its home port in Mumbai. The fire was extinguished in about two hours but the official said the sailors had not been recovered and it is unclear whether any were killed or injured. The official spoke on condition of anonymity because he was not authorized to talk to reporters.
The official said that when the blast occurred, some sailors of other nearby units jumped into the sea in panic. He says some were injured and hospitalized.
One man standing outside the dockyard who declined to give his name said he heard a sound like a rocket or jet engine, then a blast. Another witness said the sky turned red after the explosion.
Navy spokesman Narendra Vispute said efforts were being made to determine the safety of the personnel and salvage the submarine.
Indian news channel NDTV said a loud explosion was heard and a huge flame leapt up in the sky. Nearly a dozen fire engines rushed to the dockyard to douse the fire.
Afterward, the sub was nearly submerged at its berth in the naval dockyard.
Vispute said the cause of the explosion is being investigated. Further details were not available.
The 16-year-old Russian-made submarine, INS Sindhurakshak, had recently returned from Russia after undergoing an overhaul and upgrade, said Rahul Bedi, an analyst for the independent Jane's Information Group. India has 14 diesel-powered submarines, he said.
Last year, India acquired a Russian Nerpa nuclear submarine for its navy on a 10-year lease from Russia at a cost of nearly $1 billion. India also has designed and built its own nuclear submarine; the navy activated the atomic reactor on that vessel Saturday and could deploy it in the next two years.
India has steadily built up its naval capabilities in recent years, spurred by its rivalry with neighboring China.