Ukraine said its forces had struck a Russian oil depot serving Moscow's air force hundreds of kilometers from the border between the two countries.
The attack is in a series of escalating cross-border attacks by Moscow and Kiev targeting energy and military infrastructure, almost three years after the Kremlin launched its unprovoked invasion of Ukraine.
"Ukrainian defense forces hit a Russian oil depot in Engels" in the Saratov region, the General Staff of the Ukrainian army said in a statement published on social media.
"We must emphasize that this oil depot supplied fuel to the military air base, Engels-2, where the strategic aviation of the enemy is located," the announcement added.
In earlier statements, Russian officials admitted that Ukraine had attacked the region with drones.
The Russian Defense Ministry said air defense systems shot down 32 Ukrainian drones overnight, including 11 over the Saratov region.
The governor of the region, Roman Busargin, said emergency teams were deployed to an industrial building that was engulfed in flames after a Ukrainian drone strike. However, he did not give details about which building it was about.
Busargin added that there were no injuries from the attacks.
Kiev has also claimed responsibility for earlier attacks targeting oil depots, as Ukraine continues its efforts to cut off Russian energy revenues it says it uses to fund its war against Ukraine.
"The destruction of the oil depot creates major logistical problems for the Russian strategic aviation and significantly reduces its capabilities to attack peaceful Ukrainian cities and civilian facilities," the Ukrainian military said.
Meanwhile, Kiev also said that during the night the Ukrainian air defense shot down 41 Russian drones, while another 22 were shot down or disappeared from the radar after interference in their electronic systems./ REL (A2 Televizion)