A technical problem caused radioactive water that feeds a power generator on a Russian nuclear submarine to leak Tuesday, Russian news agencies reported, quoting navy officials who said the accident caused no environmental danger and did not raise radiation levels.

Crew members quickly discovered the leak on the Northern Fleet submarine at a base in the Arctic port of Vidyayevo, and authorities were trying to determine what caused it, Interfax quoted the head of the Russian navy, Adm. Vladimir Masorin, as saying.

"There is no radioactive pollution at the base," Masorin he said, warning against "dramatizing the situation."

"Such have occurred before, but they had no tragic consequences," he said, according to Interfax.

News agencies also quoted navy spokesman Capt. Igor Dygalo as saying that radiation levels inside and outside the vessel were normal. "There is no threat of pollution to the environment," ITAR-Tass quoted Dygalo as saying.

Interfax quoted an upper parliament house member and former Northern Fleet commander, Adm. Vyacheslav Popov, as saying the leak involved radioactive water used to cool the reactor.

Navy officials could not immediately be reached for comment.

Dygalo said the leak occurred while the generator was being powered up or switched off, according to ITAR-Tass and other Russian news agencies, but it was not clear which.