Updated

Two U.S. sailors died after waves swept them from the deck of a nuclear submarine off the coast of southwestern England on Friday, British coast guards said.

The USS Minneapolis-St. Paul was leaving Plymouth harbor in rough weather around midday, said Sean Brooks, a coast guard spokesman. Four sailors were tied to the vessel with ropes — a routine precaution — but two fell into the surging water.

British rescue boats picked up all four, Brooks said.

Lt. Chris Servello, a spokesman for the U.S. 6th Fleet in Naples, southern Italy, said the four men were taken to hospital in Plymouth, where two were pronounced dead. The two survivors were treated for minor injuries and discharged, he said. No one else was injured.

Coast guard spokesman Brooks said authorities received a request for assistance from the USS Minneapolis-St. Paul at 12.50 p.m. and sent a search and rescue helicopter and a lifeboat to the scene.

Brooks said that rescuers initially saw two sailors tied to the vessel's hull with ropes.

"Because of the violent weather, they were frequently plunged below the waves," he said. "It then transpired that there were already two other guys in the water."

"They managed to fish everybody out of the water," Brooks said.

Servello, the U.S. Navy spokesman, said the submarine had just completed a weeklong layover in Plymouth and was heading out to sea for routine duties.

The nuclear-powered attack submarine, which is based in Norfolk, Virginia, has a crew of 110 and can reach speeds exceeding 30 miles (47 kilometers) an hour. Its weapons include torpedoes and Tomahawk cruise missiles.

Sixth Fleet is the operational arm of U.S. Naval Forces Europe and is primarily responsible for the Mediterranean and western and central Africa.

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