Head of Russia's Republic of Bashkortostan Radiy Khabirov said the facility was undergoing repairs at the time, Ukrinform reports, citing The Moscow Times.

The official confirmed that oil-processing equipment undergoing repairs at one of the refineries was damaged.

He said the extent of the damage was currently being assessed, but claimed that repairs would be completed within several days.

Ufa Acting Mayor Rustam Sharipov said the city had been attacked by six drones, four of which were allegedly shot down, while another "fell in an industrial area," where firefighters were now "putting out a fire."

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One of Russia's largest petrochemical and refining complexes is located in northern Ufa. It includes Bashneft-UNPZ, Bashneft-Ufaneftekhim and Bashneft-Novoil, with a combined annual processing capacity of 23.5 million tonnes. It was not specified which refinery was hit.

It was also not disclosed why the facility's unit was undergoing repairs. At the same time, the publication noted that the petrochemical complex had been targeted by Ukrainian drones three times in August alone, following multiple attacks in July and June.

On August 2, drones attacked the Bashneft-UNPZ oil refinery, located more than 1,700 kilometers from the Ukrainian border.