The US Navy says Russian submarine activity in the Arctic has risen to Cold War levels—and, for the first time since the collapse of the Soviet Union, Navy surface vessels have entered the Barents Sea. The 6th Fleet said four American destroyers and a British Royal Navy vessel were in the area Monday for maritime security operations, believed to be anti-submarine exercises, NBC News reports. The Navy says its ships haven't entered the sea between Russia and Norway's Arctic coast since the mid-1980s. The sea is considered international waters. During World War II, American and British ships on the treacherous "Murmansk run" escorted shipping convoys delivering essential supplies to the Soviets.
"In these challenging times, it is more important than ever that we maintain our steady drumbeat of operations across the European theater, while taking prudent measures to protect the health of our force," the 6th Fleet said in a statement, per the Barents Observer. Russia's Northern Fleet is based in the area, and the Navy says it notified the country's defense ministry May 1 "in an effort to avoid misperceptions, reduce risk, and prevent inadvertent escalation," reports Reuters. Russia, which has been building up its forces in the Arctic, said Monday it is tracking the US and British vessels. A defense ministry statement noted that the American ships are armed with the missile defense systems Moscow wants to include in arms cuts. (Read more Navy stories.)