Photo shows the moment when a Royal Navy frigate intercepted a Russian submarine

On Sunday the Royal Navy's HMS Kent frigate ship intercepted a Russian Kilo-class submarine, after it surfaced off the Eastern coast of England.

Russia's Stary Oskol, capable of carrying torpedoes and cruise missiles, was on its way towards the English Channel.

Royal Navy

A Royal Navy photo shows the HMS Kent intercepting the Stary Oskol.

After the incident, which is the latest of many involving Russian military vehicles encroaching in NATO territory, Russian state-run media claimed that the friendly submarine was being towed by a tugboat, even waving at passing merchant ships.

However, the photo released by the Royal Navy doesn't show a tugboat at all.

In fact, Russian sub activity and sightings have increased so much that Vice Admiral James Foggo III of the US Navy wrote that the uptick was the beginning of a "fourth battle of the Atlantic."

"Not only have Russia's actions and capabilities increased in alarming and confrontational ways, its national-security policy is aimed at challenging the United States and its NATO allies and partners," Foggo wrote in the June issue of Proceedings, the US Naval Institutes monthly publication.