Russia has conducted a systematic campaign of drone surveillance against strategic NATO and European Union military installations using vessels from its so-called shadow fleet, according to a report by the International Institute for Strategic Studies (IISS). The findings, published on July 3, 2026, document 144 drone incursions into European airspace between August 2024 and February 2026, with half of the incidents directed at military sites, including locations storing U.S. nuclear bombs and a French submarine base housing ballistic missile submarines.
The report identifies a direct link between the drone operations and Russian shadow fleet vessels, which were initially created to circumvent Western oil sanctions. According to the IISS, the ships have been repurposed as launch platforms for unmanned aerial vehicles (UAVs) conducting reconnaissance over critical infrastructure, ports, energy facilities and industrial sites — accounting for a quarter of all incidents. Many flights also disrupted civilian air traffic, forcing temporary shutdowns at multiple European airports.
Drone incursions and surveillance network
The IISS assessed that the drone campaign represents a series of tactical successes for Moscow and a strategic failure for NATO’s air defense architecture. European air defense systems, designed to counter missiles and combat aircraft, proved unprepared for low-altitude, small UAVs deployed from civilian vessels. The report noted that multiple shadow fleet ships were likely involved in each operation — some launching drones, while others provided technical support and signal relay to bypass ground-based radar.
“The shadow fleet, originally built to evade oil sanctions, has become a Kremlin intelligence tool,” the IISS said in its assessment. “Blurring the line between commercial shipping and armed aggression, Russia has deployed a network in EU waters where some vessels serve as drone platforms and others as relay stations.”
The report expressed particular concern over surveillance of high-security military assets, including U.S. tactical nuclear weapons storage sites in Europe and the French strategic submarine base. The IISS warned that such operations could be aimed at undermining NATO’s nuclear deterrent posture.
European reluctance and response
For months, most EU and NATO member states avoided directly blaming Moscow for the drone incursions, despite clear geographical and temporal correlation with the presence of shadow fleet vessels. The IISS described this reluctance as a “fear of escalation” that encouraged further Russian hybrid operations.
However, the report noted that the situation changed markedly in early 2026. Once several EU countries began stopping and inspecting Russian shadow fleet ships in their exclusive economic zones, the number of drone incidents dropped sharply. “This confirmed that Russia is deterred not by international law or diplomatic statements, but by physical removal of its hybrid tools,” the IISS said.
The findings underscore the evolving nature of hybrid warfare, where commercial assets are weaponized for intelligence gathering and economic disruption. The IISS documented cases where drone incursions forced port closures, disrupted energy networks and caused millions of euros in economic damage without direct military engagement.
The report called for a coordinated allied response, including standard operating procedures for air defense against small UAVs and stricter enforcement of maritime regulations to prevent shadow fleet vessels from being used as reconnaissance platforms. The IISS assessment was based on open-source intelligence, satellite imagery and vessel tracking data.
