Documentary makers have accused Russia of having a programme to “sabotage” wind farms and communication cables in the North Sea.
Following a joint investigation, public broadcasters in Denmark, Norway, Sweden and Finland have claimed Russia has a fleet of vessels disguised as fishing trawlers an research vessels in the North Sea.
The vessels are said to carry underwater surveillance equipment and are mapping key sites for possible sabotage.
Their findings are due to be aired in Europe tonight by DR in Denmark, NRK in Norway, SVT in Sweden and Yle in Finland.
Local fishermen share sightings
Local fishermen have previously shared their own sightings of suspected Russian ships.
On April 10, Macduff fisherman John Clark posted on social media a picture of a unmarked “Russian” ship.
At the time Mr Clark said: “The ship just passed me in Atlantic, no AIS no name number and no flag not even answering VHF16 strange looking ship.”
The BBC said it understands that UK officials are aware of Russian vessels moving around UK waters as part of the communications plan.
In the documentary, a Danish counter-intelligence officer claims the sabotage plans are being prepared in case of a full conflict with the West, while the head of Norwegian intelligence told the broadcasters the programme was considered highly important for Russia and controlled directly from Moscow.
The broadcasters say they have analysed intercepted Russian communications which indicate so-called ghost ships sailing in Nordic waters which have turned off the transmitters so as not to reveal their locations.
Russian ship in Moray Firth
The report focuses on a Russian vessel called the Admiral Vladimirsky. Officially, this is an Expeditionary Oceanographic Ship, or underwater research vessel. But the report alleges that it is in fact a Russian spy ship.
The documentary uses an anonymous former UK Royal Navy expert to track the movements of the vessel in the vicinity of seven wind farms off the coast of the UK and the Netherlands on one mission.
It says the vessel slows down when it approaches areas where there are wind farms and loiters in the area. It says it sailed for a month with its transmitter turned off.
When a reporter approached the ship on a small boat, he was confronted by a masked individual carrying what appeared to be a military assault rifle.
The same ship was reportedly sighted off the Scottish coast last year.
It was spotted entering the Moray Firth on November 10 and seen about 30 nautical miles east of Lossiemouth, home to the RAF’s Maritime Patrol Aircraft fleet before heading slowly west.
This comes as the Russian-flagged ‘Nikolay Chiker’ vessel was sighted near Shell’s Brent field and the CNR International-operated Ninian platform off the east of the Shetland islands.