Russian spy ship detected off U.K. as British official warns Putin: “We know what you’re doing”

British Defense Secretary John Healey told Parliament on Wednesday the Royal Navy was tracking a “Russian spy ship” that passed through U.K. waters, warning Russia’s President Vladimir Putin: “We know what you’re doing.”

Healey said the Yantar vessel was being “used for gathering intelligence and mapping the U.K.’s critical underwater infrastructure.”

“I also wanted President Putin to hear this message: We see you, we know what you’re doing and we will not shy away from robust action to protect this country,” he told lawmakers.

The ship entered British waters on Monday about 45 miles off the country’s coast, with the Royal Navy dispatching two vessels to monitor it, Healey said.

“It was detected loitering over U.K. critical undersea infrastructure,” the defense minister said.

He added the ship was now in the North Sea, “having passed through British waters.”

Healey said a Royal Navy submarine was authorized to surface close to the Yantar “strictly as a deterrent measure” and “to make clear that we have been covertly monitoring its every move,” BBC News reported.

Healey said it was the second time the Yantar had been detected in British waters recently, after it was also spotted in November.

British warships have tracked Russian navy vessels on several occasions in recent months.

Earlier this month, the Royal Navy revealed that in late December the frigate HMS Somerset had tracked a Russian naval group as it sailed from the North Sea to the English Channel, although the group had stayed in international waters.

In November, British jets were scrambled to monitor a Russian reconnaissance aircraft flying close to U.K. airspace, just days after NATO jets were mobilized when Russian aircraft were spotted over the Baltic Sea and off the coast of Norway.

In September last year, Royal Navy warships spent a week “closely shadowing” four Russian vessels in U.K. waters, while two Royal Air Force jets scrambled to intercept two Russian aircraft operating near the U.K., the navy said in a press release.

Also in September, the U.S. Coast Guard said that it tracked a group of Russian naval vessels, including two submarines, as they crossed into U.S. waters off Alaska in an apparent effort to avoid sea ice.

The month before that, a U.S. Coast Guard cutter on routine patrol around Alaska’s Aleutian Islands came across a Russian ship in international waters but within the U.S. exclusive economic zone.