Ukraine air defences shot down 29 out of 38 Iranian-made Shahed drones launched from Russian territory, the air force said.
The air force said in a statement the attack on several Ukrainian regions lasted from 8 p.m. (1800 GMT) on Friday to 4 a.m. on Saturday.
The energy ministry said 416 settlements in the Odesa region in the south and in the Zaporizhzhia region in the southeast were cut off from electricity after networks were damaged in the strikes.
Last winter, Russia pounded Ukraine with hundreds of missiles and drones, leaving millions without electricity, heating, and water during the coldest months.
This year Ukraine had an unusually warm autumn. But as temperatures start to fall, officials have urged residents and businesses to prepare for renewed Russian attacks. “We do not have a right to relax,” Volodymyr Kudrytskiy, head of the power grid operator Ukrenergo, told Ukrainian TV. “Certainly, all of us, energy workers and defence forces, are preparing to repel possible Russian attacks on the energy infrastructure this winter.”The energy ministry also said an oil refinery was hit in the Odesa region. An administrative building was also damaged and one civilian was wounded in the strike, the south military command said in a statement on the Telegram messaging app. In Ukraine’s northern Chernihiv region on the border with Russia and Belarus, two infrastructure buildings were damaged during the overnight strike, the military said. The energy ministry said six settlements were without power in the Chernihiv region.The drones also targeted Kyiv in the second attack so far this month, officials said, adding that all drones heading to the capital were shot down on their approach.