Drones attacked the Lukoil-Nizhegorodnefteorgsintez refinery in Kstovo in Russia’s Nizhny Novgorod region.
A fire broke out at the facility after the attack. Reuters later reported, citing two industry sources, that the CDU-6 primary refining unit had been shut down.
According to Reuters, the unit accounted for around 53% of the refinery’s processing capacity.
The Kstovo plant is one of Russia’s largest oil refineries.
Ukraine has significantly increased attacks on Russian refining and oil-transport infrastructure in recent months, describing such facilities as part of the economic infrastructure supporting Russia’s war effort.