Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Russia: Nuclear Reactor Safe on Fire-Hit Submersible Associated Press MOSCOW - The nuclear reactor on one of the Russian navy's research submersibles hasn't been damaged in a fire that killed 14 seamen, Defense Minister Sergei Shoigu said Thursday, adding that the vessel would be put back into service after repairs. The Defense Ministry said the 14 seamen were killed by toxic fumes from Monday's blaze, the navy's worst accident in more than a decade. It said some others survived the blaze, but there was no information on how many crew members have been rescued. The ministry didn't name the vessel, and the Kremlin refused to divulge any details about it, saying the information is highly classified. Russian media reported that it was the country's most secret submersible, a nuclear-powered research submarine called the Losharik intended for sensitive missions at great depths. Replying to questions from President Vladimir Putin about the nuclear reactor's condition, Shoigu said the vessel was designed so that its reactor is fully isolated and autonomous. "The crew also has taken all the necessary action to safeguard the reactor, and it is fully operational," he said. "That gives us hope that the vessel could be repaired quickly." Shoigu, who traveled to the navy's main Arctic base of Severomorsk Wednesday to oversee a probe into the fire, said the blaze erupted at the vessel's battery compartment and spread further. He praised crew members for "heroic" actions, saying those who died sacrificed their lives to rescue a civilian expert and to save the ship. Hundreds of sailors gathered Thursday at Russia's main naval cathedral in Kronshtadt just off St. Petersburg in the Gulf of Finland to mourn the dead.