Evidence Pack: Analyzing the IISS Report on Covert Drone Surveillance of European Nuclear Sites

Over an 18-month period beginning in late 2024, a coordinated drone surveillance campaign systematically targeted nuclear and military infrastructure across more than a dozen European nations. According to a comprehensive analysis published by the International Institute for Strategic Studies (IISS), researchers documented 144 suspected drone incursions over highly sensitive sites. The evidence pack compiled by the IISS suggests that Russian intelligence orchestrated the operation, utilizing unconventional launch methods to bypass traditional border security and early warning systems.[1][2]

The primary claim advanced by the report is that the surveillance drones were not launched from within European borders, but rather from civilian vessels operating in international waters. Specifically, investigators point to Russia's "shadow fleet"—a network of aging oil tankers with opaque ownership structures originally assembled to evade economic sanctions. By repurposing these commercial ships as mobile launch platforms, operators were able to deploy unmanned aerial vehicles (UAVs) close to European coastlines while maintaining plausible deniability.[1][3]

The evidence linking these civilian vessels to the drone incursions relies heavily on the correlation of maritime tracking data with inland drone sightings. For example, during a cluster of drone detections over French and Belgian military sites in late 2025, IISS researchers tracked multiple Russia-linked shadow fleet vessels loitering between 60 and 120 miles offshore in the North Sea. The proximity of ships like the Hav Dolphin to the targeted coastlines aligned precisely with the flight paths and estimated ranges of the drones observed inland.[1][2]

The targets of this surveillance campaign were exclusively strategic in nature. Flight logs and visual sightings confirm that drones repeatedly breached the airspace over critical nuclear and military installations. Among the most prominent sites were the UK's RAF Lakenheath—which was being prepared to house US nuclear weapons—and France's Île Longue base in Brittany, the home port for the French navy's nuclear-powered ballistic missile submarines. Additional incursions were recorded over bases in Belgium and the Netherlands where air-launched nuclear weapons are stored.[1][4]

The campaign exposed a significant structural vulnerability in the current European security architecture: the inability of traditional air defenses to effectively counter small, low-flying threats. NATO's legacy radar systems and surface-to-air missile batteries are highly optimized for detecting high-speed fighter jets and ballistic missiles. They frequently struggle to filter out the small radar cross-sections of slow-moving reconnaissance drones, such as the Orlan-10, which can remain airborne for up to 12 hours and cover distances of 300 miles.[2]

Consequently, the IISS report concluded that the intelligence-gathering operation was conducted with "substantial impunity." Despite 144 documented incidents and repeated sightings over highly restricted airspace, Western militaries did not capture or shoot down a single drone during the peak of the campaign. European governments reportedly hesitated to engage the drones kinetically due to the difficulty of intercepting them safely over populated areas, combined with a reluctance to escalate tensions over unarmed reconnaissance platforms.[1][3]

However, the operational environment shifted significantly in early 2026. As the pattern of shadow fleet involvement became clear to Western intelligence agencies, European naval forces began actively tracking, intercepting, and detaining suspicious commercial vessels operating near their territorial waters. This increased maritime pressure directly correlated with a sharp decrease in drone incursions, providing further circumstantial evidence that the shadow fleet was the primary launch vector for the surveillance campaign.[3]

From a strategic perspective, defense analysts view this 18-month operation as a textbook execution of hybrid warfare. By utilizing unarmed drones and civilian ships, the operators remained deliberately below the threshold that would trigger a collective military response under NATO's Article 5. The campaign successfully mapped logistical routes, tested the reaction times of base security, and exerted psychological pressure on European governments without firing a single shot.[2][5]

The transparent publication of this evidence pack marks a turning point in how European nations are addressing the threat. Acknowledging the gap in their defensive posture, military planners are now accelerating the procurement of specialized Counter-UAS (C-UAS) technologies. Investments are being redirected toward advanced electronic warfare jammers, directed energy weapons, and localized radar systems designed specifically to detect and neutralize low-cost asymmetric threats, ensuring that critical infrastructure is hardened against future surveillance operations.[5]