MOSCOW: A fire broke out on Saturday at an oil refinery in Russia's Samara region following a drone attack, the regional governor said.
"Last night, there were several drone attacks against regional oil refineries," Governor Dmitri Azarov said in a regional government statement published on Telegram.
One of those attacks caused a fire at the Kuibyshev oil refinery, he added, noting that there were no casualties.
The refinery, run by Russian oil giant Rosneft, is one of the largest in the Samara region, with a production capacity of 7 million tonnes of oil per year, according to its official website.
A drone attack on another refinery in Samara, Novokuibyshevsk, "was repelled without damaging the technological equipment", according to Azarov.
"We see that the enemy, who is suffering defeats on the battlefield, is doing everything possible to undermine our endurance and unity," he said.
Separately, the Russian defence ministry said in a press release that it had neutralised overnight "12 Ukrainian drones" over the regions of Bryansk, Belgorod and Voronezh, all three of which border Ukraine, as well as over the region of Saratov.
Ukraine, which has been facing a Russian offensive for two years, has stepped up its attacks inside Russia in recent weeks, targeting energy sites in particular.
Kyiv had promised to bring the fighting to Russian soil in retaliation for the numerous bombardments on its territory.