Story highlights U.S. spy satellites, aircraft and submarines tracked a Russian ship all the way down the coast to Cuba

The U.S. has watched for the last several months as Russian submarines in deep water have come close to the undersea cables

Washington (CNN) When a Russian military ship called the Yantar suddenly crossed the Atlantic and started moving down the East Coast of the United States last month, it set off alarm bells inside the world of U.S. naval intelligence.

U.S. spy satellites, aircraft and submarines tracked the ship all the way down the coast to Cuba, according to two U.S. defense officials.

It had been years since the U.S. had seen this type of activity by the Russians, officials said. While the Russians have insisted the Yantar is not a spy ship, U.S. naval intelligence believes it has one significant and unsettling capability: small underwater vehicles that can cut vital undersea cables carrying vast amounts of commercial and military data, voice communications and Internet service between the U.S. and Europe.

Some of these details were first reported by the New York Times.

U.S. officials told CNN there was no indication that the Russians have any intention of cutting the cables, but they said that they are showing off their capability to U.S. naval intelligence by their actions.

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