Drone Strikes Hit Russian Defence Infrastructure Across 11 Regions
Russia was subjected to one of the largest aerial assaults of the war late on May 20 and into the early hours of May 21, as waves of unmanned aerial vehicles (UAVs) struck targets across at least eleven regions.
The Russian Ministry of Defence reported that 159 drones were intercepted, though independent estimates suggest the true number may have exceeded 300. The strikes, widely attributed to Ukrainian forces, focused on military and industrial infrastructure—particularly sites critical to Russia’s defence production.
The most significant damage was reported in Bolkhov, Oryol Oblast, where a drone strike hit a facility producing microelectronics used in military applications. The plant is reported to manufacture semiconductors, batteries, and microchips essential for Russian communications, missile guidance, and electronic warfare systems. Footage circulating on social media showed a large explosion and a fire at the site, though Russian officials attempted to downplay the scale of the incident.
In Tula Oblast, regional authorities confirmed that falling debris from intercepted drones caused damage to residential buildings in the city of Tula.
Governor Alexei Dyumin stated that this was the tenth wave of drone attacks targeting the region, which hosts multiple arms production sites including the Tula Cartridge Works and Splav, a manufacturer of multiple rocket launcher systems.
Moscow Region was also affected. Six drones were reportedly shot down near the capital, prompting the temporary closure of Vnukovo, Sheremetyevo, and Domodedovo airports. Airspace over the region was restricted for several hours, leading to flight delays and diversions.
The Kremlin’s air defense systems were visibly active, and local media reported explosions in the sky above several suburbs. Other affected regions included:
- Bryansk and Kursk – frequent targets due to their proximity to the Ukrainian border and hosting military logistics hubs;
- Belgorod and Lipetsk – regions with known fuel depots and vehicle repair centers;
- Ryazan and Vladimir – key railway junctions and storage facilities;
- Kaluga and Oryol – home to several defence contractors and supply chain nodes.
In multiple areas, mobile networks were temporarily disabled to prevent drones from using GPS or cellular triangulation for navigation. This tactic, increasingly employed by Russian authorities, also disrupted civilian communications.
The Russian Ministry of Defence maintained that all drones were either destroyed or diverted, and that no critical infrastructure suffered significant damage. However, open-source intelligence and local footage contradict these claims in several locations.