MOSCOW -- The Russian government said Monday that leaky torpedo fuel caused the explosions that destroyed the Kursk nuclear submarine, wrapping up nearly two years of sensitive investigation into one of the country's worst post-Soviet disasters.
The announcement that the vessel was destroyed by an internal malfunction -- and not a foreign submarine as had once been theorized -- was an uncomfortable admission for Russia's struggling military. The Kursk was one of the navy's most advanced submarines when it sank in the Barents Sea in August 2000, killing all 118 men aboard.
Industry and Science Minister Ilya Klebanov, who led the commission investigating the disaster, said a leak of hydrogen peroxide used to fuel the 65-76 Kit (Whale) torpedo was at fault, according to the Interfax news agency. The conclusion was reached unanimously at the commission's last meeting Saturday, Klebanov said.
"The reason for the accident was a thermal explosion of torpedo fuel components. It occurred as a result of a leak of hydrogen peroxide and the ignition of materials in the torpedo apparatus," Klebanov was quoted as saying.
The torpedo fuel caused one explosion that killed all crew members in the submarine's first compartment and some in the next compartment, another commission member, parliament member Vice Admiral Valery Dorogin, was quoted by Interfax as saying.
Then the fire and increase in pressure caused other ammunition on the submarine to detonate, resulting in a huge, second explosion, signaling doom for the entire craft, he said.
Outside observers, including U.S. and Russian experts, had long ago reached the same conclusion about what destroyed the Kursk. But the Russian government investigation dragged on, and Russian officials refused to rule out the theory of a collision with a foreign submarine -- possibly American or British -- until recently.
Klebanov's office refused to comment Monday on the announcement, and calls to Dorogin's office went unanswered.
"We knew this a long time ago," said Igor Kudrin, a former submarine officer who heads the Submariners' Club in St. Petersburg, a relief organization of mostly retired officers that has lobbied on behalf of the victims' families.
While Kudrin said it was some comfort that the commission agreed with other experts' findings, he added it "will not put an end to the Kursk story for the relatives."
Russia has already pulled from service all torpedoes of the type that malfunctioned, which use highly volatile hydrogen peroxide for a propellant and have reportedly been used since the early 1970s. The torpedoes have a higher speed and range than conventional torpedoes powered by electric engines -- advantages that, according to Russian news reports, prompted the Navy to neglect concerns about its unstable fuel.
President Vladimir Putin's handling of the Kursk disaster was considered his first major blunder in his presidency. He stayed on vacation after it happened and did not comment on it publicly for several days.
The government hesitated for several days before accepting foreign offers of help, while Russian submersibles were unsuccessful in attaching themselves to the Kursk's escape hatch.
When foreign divers reached the Kursk a week after the catastrophe, it took them only hours to open the hatch. The public later learned with dismay that the navy had dismissed its own deep-sea divers years before the disaster as a money saving measure.
The commission's investigation was largely based on study of the bulk of the Kursk's wreckage, which was lifted in an international operation last October.
During the salvage effort, the front section of the Kursk was cut off out of fear it could break off while being raised, and it remains on the floor of the Barents Sea. Dorogin told Interfax that the commission had decided that the remains of the submarine should be blown up.