Russian online sources report that attack drones hit an oil refinery in the Kaluga Region.
Local residents heard the distinctive sounds of a UAV flying overhead, followed by explosions and a fire in the Dzerzhinskyy district.
The Pervy Zavod refinery has already come under attack this spring. On 15 March, as a result of a special operation conducted by the DIU, the enterprise suffered damage from drones. According to the Defence Intelligence, the plant is used by the Putin regime for military purposes.