MOSCOW (AP) -- Russian news agencies say authorities have charged a sailor with fatal negligence in the deaths of 20 people aboard a nuclear submarine this month.
The state-run RIA-Novosti news agency says Dmitry Grobov faces up to five years in prison if convicted.
Authorities have accused Grobov of setting off a fire-extinguishing system aboard the newly built submarine during a test run in the Sea of Japan on Nov. 9.
Officials say liquefied Freon gas poured into part of the submarine.
Despite the charge, Russia's top federal investigator was quoted as saying investigators are still examining the possibility of other causes, including a problem with the submarine's fire-suppression system.
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