Researchers said the Kremlin ran a Vladimir Putin shadow tanker drones campaign for 18 months, using drones launched from shadow fleet vessels to watch nuclear sites in the UK, France, Belgium and the Netherlands. The IISS counted 144 incidents in more than a dozen countries, with drones also seen over airbases and airports.
Charlie Edwards, a senior IISS fellow, said: "every government we spoke to said they would welcome the report being published". He also said: "It is our assessment that it is highly likely that the Kremlin conducted a coordinated UAV [unmanned aerial vehicle] campaign over Europe" and described it as "a series of tactical successes for the Kremlin" and "a strategic failure of allied defences".
IISS counts 144 incidents
The pattern mattered because it was not a single flight over one site. The IISS analyzed 144 incidents beginning in late 2024 and said the activity continued into November and December 2025. Researchers said Russian intelligence had operated with substantial impunity, and western militaries did not capture or shoot down any of the drones.
Unusual drones flew low into RAF Lakenheath, RAF Fairford in Gloucestershire and at least two other US air force bases in England in late November 2024. Researchers said the drones may have been piloted from the Seasons 1 tanker in the North Sea near Essex or the Hav Dolphin cargo vessel that was sailing towards Hull docks at the time. The Hav Dolphin was also suspected of being behind drone sightings at a submarine base in northern Germany the following May.
France, Belgium and the Netherlands
Five drones were detected over France’s Île Longue base in December 2025. Three Russia-linked shadow fleet vessels were between 60 to 120 miles off shore at the time. Drone incursions in November and December 2025 over Kleine-Brogel airbase in Belgium and Volkel in the Netherlands occurred while Russia-linked shadow fleet vessels were in international waters in the North Sea.
Researchers said RAF Lakenheath in Suffolk and France’s nuclear submarine base at Île Longue in Brittany were among the sites targeted by unarmed drones believed to have been launched at sea. The report also said drone control techniques first learned during the war in Ukraine may have been used by other ships acting as recovery vessels or signal repeaters.
Kremlin, Nato and Europe
Charlie Edwards said it was highly likely that the Kremlin conducted a coordinated UAV campaign over Europe spanning more than a dozen Nato countries and Ireland. European governments were reluctant to accuse Russia publicly, even as the IISS said the Kremlin most likely conducted the coordinated campaign. Edwards said the report would still be welcomed: "every government we spoke to said they would welcome the report being published".
The open question is who physically operated the drones from the shadow fleet vessels and what evidence tied those ships to the flights. The report does not name that crew, and it does not record any arrest or public accusation after the flights into the UK, France, Belgium and the Netherlands.
