Ukraine’s Air Force says Russian forces launched 137 strike drones overnight from multiple directions, including Bryansk, Oryol, Kursk, Millerovo, and Crimea. Most of the drones were intercepted by air defense, electronic warfare, aviation units, and mobile fire groups.

Explosions were reported in Russia’s Oryol city and Stavropol Krai overnight on December 4, following drone attacks. In Nevinnomyssk, a chemical plant—one of Russia’s largest producers of nitrogen fertilizers, ammonia, and raw materials for explosives—caught fire.

A large fire broke out at an oil refinery in Livny, Oryol region, Russia, on December 2 following an attack by unknown drones, local authorities and residents reported. Two refinery terminals are reportedly ablaze.

Ukraine launched a wave of strikes on major energy facilities inside Russia overnight, hitting regions far from the front line and causing explosions and temporary blackouts, according to Russian officials and local media reports.

An Mi-8 helicopter crashed in Russia’s Oryol Region during a routine flight, according to a spokesperson for the Moscow Military District.