NATO allies reportedly disrupted a covert Russian operation in Arctic waters this spring after detecting Russian submarines conducting exercises involving technology that could potentially be used against important undersea communication cables.
According to two Western officials, the activity involved Russia's GUGI undersea warfare directorate. Deep sea submersibles were reportedly used during the operation to practise deploying an advanced system capable of damaging underwater infrastructure while making it difficult to identify those responsible.
British, Norwegian and American forces monitored the Russian vessels and confronted them during the operation, the officials said. The Russian units were unable to complete the exercise and later moved away from the area.
Britain and Norway had revealed in April that they had discovered a secret Russian operation in Arctic waters. However, details about the technology involved, the precise location and the participation of the United States had not previously been made public.
The incident comes as Western intelligence agencies remain concerned about a possible increase in Russian sabotage activities across Europe. Some officials believe Moscow could be preparing for a wider confrontation with NATO.
Three US officials said some American intelligence analysts are increasingly worried that Russia could attempt to challenge NATO's collective defence commitment under Article 5. Western officials said attacks against underwater communication networks could form part of such an effort.
Undersea cables are essential to modern communications and international commerce. Although many are relatively thin and rest directly on the ocean floor or just beneath it, they carry a large share of the world's internet traffic and support financial transactions between countries.
These cables have also been strategically important during previous conflicts. During the First and Second World Wars, underwater communication links played an important role in transmitting information through telegraph and telephone networks.
Two fibre optic cables connecting Svalbard with mainland Norway extend for around 1,400 kilometres each. Some sections of the cables are located at depths of up to approximately 2,700 metres below the ocean surface.
Russia's Defence Ministry did not respond to questions about the reported incident. The Kremlin has repeatedly rejected accusations that it carries out sabotage in NATO countries or is seeking a direct confrontation with the alliance.
Some Western officials believe Russian targeting of European countries has become more frequent in recent months, while the situation along the Ukraine battlefield has remained largely unchanged.
Poland, Lithuania and Romania have reported different incidents involving alleged violations. In the latest case mentioned by officials, an attempted drone attack near Leipzig and Halle Airport in August led Germany to take several measures, including shutting down a Russian consulate in Bonn and a cultural centre in Berlin.
In August, CIA Director John Ratcliffe travelled to Moscow and met intelligence officials there. Two people familiar with the visit said one purpose of the trip was to warn Russia against increasing sabotage activity in Europe.
Reuters was unable to establish whether Ratcliffe specifically discussed Russia's secret activities involving undersea operations. The Kremlin did not provide details about the discussions or explain what issues were raised during the meetings.