Ukrainian drones attacked energy facilities in Russia's Astrakhan and Volgograd oblasts overnight on Feb. 3, causing fires, according to local authorities.
The news comes as Ukraine ramps up long-range strikes against Russian energy infrastructure to stifle Moscow's gas and oil exports that fuel its war chest.
Russian air defenses "repelled a massive attack against Volgograd Oblast," Governor Andrei Bocharov claimed.
"Most of the drones were intercepted and neutralized. There were no casualties. Fallen debris caused fires on the territory of a local oil refinery," the governor said in a statement, reporting short-term voltage drops in the power grid.
Volgograd residents reported at least 50 explosions during the night, with almost all of the drones intercepted over the local Lukoil oil refinery, the Russian Telegram channel Baza reported.
The Lukoil refinery in Volgograd Oblast lies around 500 kilometers (300 miles) from the front line in Ukraine and was previously targeted by Ukrainian drones on Jan. 31.
In Astrakhan Oblast, air defenses and electronic warfare systems were deployed to intercept drones attacking fuel and energy facilities, Governor Igor Babushkin claimed.
"A fire broke out after a crash of one of the drones," Babushkin said on his Telegram channel without specifying the exact location of the fire while reporting no casualties. Baza claimed that the fire broke out at the Astrakhan Gas Processing Plant.
"The Astrakhan Gas Processing Plant was attacked. This is one of Russia's key energy facilities, which is used to process gas condensate and produce gasoline, diesel fuel, and more," said Andrii Kovalenko, the counter-disinformation chief at Ukraine's National Security and Defense Council.
Astrakhan Oblast is located in southwestern Russia on the Caspian Sea coast and borders Kazakhstan. The city of Astrakhan is almost 800 kilometers (500 miles) from the front line in Ukraine.
Russian air defenses intercepted 70 Ukrainian drones overnight, including 27 over Rostov Oblast, 25 over Volgograd Oblast, seven over Astrakhan Oblast, five over Voronezh Oblast, four over Belgord Oblast, and two over Kursk Oblast, the Russian Defense Ministry claimed.
Nine Russian airports temporarily halted operations amid the drone strikes.
The Ukrainian military has not commented on the claims, which could not be independently verified.