Editor's note: The story was updated with new information from Ukraine's General Staff.
Fires broke out at two oil depots in Russia's Voronezh Oblast and Perm Krai overnight on Oct. 4, local authorities reported.
According to the Russian Defense Ministry, its air defense downed six Ukrainian drones over Voronezh Oblast, six over Belgorod Oblast, one over Rostov Oblast and one over the Azov Sea.
Ukrainians soldiers attacked the Annanefteprodukt fuel and lubricants storage base near the village of Anna in Voronezh Oblast, Ukraine's General Staff said. It was not specified what kind of weapon was used in the attack.
A source in the Security Service of Ukraine (SBU) told the Kyiv Independent later that the oil depot was struck with drones operated by the SBU.
According to the source, the oil storage facility housed 20 tanks with fuel and lubricants.
"It was confirmed that at least one of the vertical tanks was hit," the General Staff said.
Aleksandr Gusev, Voronezh Oblast governor, claimed that an empty tank at an oil storage facility was hit during the drone attack and put out later.
A large-scale fire also broke out at an oil depot in the village of Osentsy in Perm Krai. Russia's Perm Krai lies around 1,800 kilometers northeast of Ukraine.
The fire engulfed fuel tanks and spread over 10,000 square meters, the Russian Emergency Situations Ministry reported.
No casualties were reported in both regions.
The Kyiv Independent could not verify Russia's claims.
In recent months, Ukrainian forces have launched a series of drone strikes aimed at damaging Russia's oil industry, whose profits fuel Moscow's war efforts.