A Russian warship and aircraft escorted an American destroyer in the Pacific Ocean, the Ministry of Defense in Moscow said on Thursday, after the U.S. Navy said it had sailed near contested waters in the Sea of Japan.

Russia played down the incident, which a U.S. official told CNN took place Wednesday and was the first time the American navy had carried out a “freedom of navigation operation” in that area since the Soviet era in 1987.

The USS McCampbell didn’t go closer than 100 kilometers (60 miles) to Russian territorial waters, the Ministry of Defense said in an emailed statement. “If the American destroyer’s crew demonstrated anything, it was its unsuccessful attempt to escape at full speed from Pacific Fleet forces escorting it,” it said.

The warship sailed close to the Peter the Great Bay, home to the city of Vladivostok and the Russian Pacific Fleet, according to the U.S. Navy. The U.S. doesn’t recognize Russia’s claim to the waters, it said.