Unmanned aerial vehicles (UAVs) of the Armed Forces of Ukraine attacked one of Russia’s largest oil refineries in Yaroslavl and the “Promsintez” explosives plant in the Samara region. According to monitoring channels Exilenova+ and Supernova+, on the night of March 28, the Yaroslavl refinery was hit multiple times, causing fires to break out on the premises. Eyewitnesses on social media reported that the drones approached the target from the northwest, flying over the city before striking the industrial zone.
At the same time, the Promsintez plant in Chapayevsk, Samara region, one of Russia’s largest explosives producers, was targeted. According to the OSINT channel “KiberBoroshno,” the attack was carried out using a long-range Ukrainian FP-5 “Flamingo” missile: a photo of the missile was published, and video footage of the strike in the production area—where explosive materials are synthesized—was geolocated. ASTRA analyzed videos from social media and concluded that the strike hit the Chapayevsk industrial hub, which houses two defense enterprises: JSC “Promsintez” (producing TNT, ammonites, nitrobenzene) and JSC “Polymer” (weapons, ammunition, explosives). Eyewitnesses reported multiple explosions, and police blocked access to the industrial sites after the attack, according to ASTRA.
The Yaroslavl refinery (LLC “Slavneft-YANOS”) is among Russia’s five largest refineries by capacity, capable of processing over 15 million tons of oil per year. The facility supplies fuel to both the civilian market and the Russian military—Ukraine’s General Staff previously stated that it contributes to military logistics. The site has been repeatedly targeted by drone attacks, in January 2024 and December 2025.
Promsintez has also been attacked before: in March and April 2025, drone strikes forced the plant to suspend operations. On the night of March 22, 2026, a drone hit the roof of one of the workshops, causing a fire.
