Ukraine has targeted two of Russia's oil refineries in drone strikes in an effort to bankrupt their ability to continue funding the war.

Late Tuesday night or early Wednesday morning, Ukrainian drones struck the Nizhny Novgorod oil refinery in Kstovo, in central Russia 520 miles from the front line in northern Ukraine. The blasts triggered what the Ukrainian general staff in Kyiv described as a “powerful” fire that burned through the early morning.

Ukraine said on Wednesday it had struck a big Russian oil refinery in an overnight drone attack, and a Russian official said an attempted Ukrainian drone strike on a nuclear power plant had been thwarted.