The Russian city of Saratov was targeted by a Ukrainian drone overnight, the regional governor said on Friday, saying drone debris had fallen in an industrial zone after it had been destroyed.

Ukraine launched a drone attack on a Russian chemical plant in the western city of Tula overnight on Friday into Saturday, according to the country’s security service. Russian authorities have not acknowledged the attack.

The city hosts the Saratov Oil Refinery, formerly known as the Cracking Plant, which is part of Rosneft, the state-run oil company