Overnight, Russian drones attacked Ukrainian electricity infrastructure as it prepares for winter. File Photo by Bonnie Cash/UPI | License Photo

Oct. 8 (UPI) -- Russian drones attacked and seriously damaged a Ukraine thermal power plant overnight, authorities announced Wednesday.

Two workers were injured in the attack, said DTEK, Ukraine's largest electric company. The location of the plant was not disclosed.

The attacks also struck energy infrastructure in the northern Chernihiv, southern Kherson and southeastern Dnipropetrovsk regions, authorities said. These attacks on heat sources come annually in preparation for winter. Similar attacks left millions of Ukrainians without electricity last year.

DTEK posted on X that a coal-enrichment plant was attacked in the Donetsk region. The plant was destroyed but there were no injuries.