A frigate, aircraft and hundreds of personnel took part in an operation to monitor a Russian attack submarine and two spy submarines near undersea infrastructure in the North Atlantic.
The purpose was to send a message to Russia, British Defence Secretary John Healey said at a press conference:
We see your activities across our cables and pipelines, and you should know that any attempt to damage them will not be tolerated and will have serious consequences.
After a month of surveillance, the Russian submarines left the area.
