Ukrainian drones attacked a gas plant in Russia’s Orenburg region, the local governor said on Sunday, causing a fire to break out at a workshop which emergency services were working to put out.

The governor, Yevgeny Solntsev, said on his official Telegram channel that none of the plant’s employees were hurt in the attack, which left the plant partially damaged.

Solntsev said earlier this month that Ukrainian drones had tried to attack an unnamed industrial facility in the Russian city of Orsk near the border with Kazakhstan.

Unverified video posted to Telegram at the time showed an object smashing into a facility identified as the Orsknefteorgsintez oil refinery in Orsk.

Ukraine has stepped up its attacks on Russian refineries and other energy facilities since August to try to disrupt petrol supplies and deprive Moscow of funding.