The British government issued a warning to the Kremlin on Wednesday, following reports that a Russian military vessel had entered U.K. waters and aimed lasers at British pilots.

Defense Secretary John Healey informed journalists in London that this was the ship’s second incursion into U.K. waters this year, with the first occurrence happening in January.

“The Yantar is currently on the fringes of U.K. waters, north of Scotland, having ventured into the broader U.K. maritime zone in recent weeks,” he stated at a press conference held at Downing Street.

The U.K. military has dispatched a Royal Navy frigate and Royal Air Force aircraft to closely “monitor and track the movements of this ship, during which the Yantar directed lasers towards our pilots,” he elaborated.

He labeled the use of lasers as “extremely hazardous” and conveyed a message to Russian President Vladimir Putin.

“We are aware of your actions. We understand what you’re up to. If the Yantar heads south this week, we are prepared.”

Healey described the Yantar as “part of a Russian fleet aimed at threatening our underwater infrastructure as well as that of our allies.”

The increasing apprehension among Britain and its NATO allies regarding the threats posed by Moscow to offshore infrastructure has intensified, particularly in light of recent sabotage incidents involving several undersea telecommunications and power cables.

Analysts and political figures have accused Russia of conducting a hybrid warfare campaign against the West as tensions escalate over the situation in Ukraine.