A major fire broke out at a refinery in Kstovo, Russia, early Wednesday after a reported drone strike, in what appears to be the latest Ukrainian attack on Russian energy infrastructure deep inside the country.

Imagery from the scene showed a large blaze burning at the refinery complex in Kstovo, in the Nizhny Novgorod region east of Moscow. Faytuks Network analysts quickly geolocated the blaze.

There was no immediate official word on casualties or the full extent of the damage. Still, the scale of the fire suggests a significant strike on or near the refinery site.

Kstovo has been hit before. The NORSI refinery in the region, one of Russia’s largest, was struck earlier this year and forced to suspend operations. The wider industrial area has also faced previous drone attacks, including strikes that disrupted petrochemical activity and fuel-related infrastructure.

The latest incident fits a broader pattern that has defined much of Ukraine’s long-range strike campaign. Russian refineries, fuel depots and petrochemical plants have been hit again and again as Kyiv tries to pressure the infrastructure that supports Russia’s military and energy economy.

In recent months, fires and shutdowns have followed strikes on multiple energy sites across Russia. Those attacks have stretched from southern facilities to key inland refineries, showing that targets far from the front remain exposed.