Russian strikes across Ukraine have killed three people and left more than 100,000 households without power, Ukraine said.
Russian forces significantly damaged gas transport infrastructure in the Poltava region and struck, the energy ministry said.
The Kharkiv region was also hit overnight, as were the regions of Zaporizhzhia and Donetsk, it said.
It called the attack a "deliberate policy of destroying Ukraine's civilian infrastructure on the eve of the heating season," hampering the heating supply system ahead of colder autumn days.
A farm in the southern Kherson region was damaged as a result of heavy shelling, killing two employees there, and an 81-year-old woman died in an overnight attack on the regional capital, local officials said.
Russia launched a massive drone attack on energy and gas transport infrastructure across six Ukrainian regions overnight, Ukrainian officials said.
In recent weeks, Russia has stepped up attacks on Ukrainian gas production and import infrastructure despite efforts by US President Donald Trump to end the war in Ukraine.
"We regard the Russian attacks as a continuation of the Russian Federation's deliberate policy of destroying Ukraine's civilian infrastructure ahead of the heating season," the energy ministry said.
Ukraine had faced a serious gas shortage since Russian missile strikes earlier this year prompted a 40% drop in production.
Ukraine's energy ministry said last week that energy facilities had been attacked 2,900 times since March 2025.
The attack on Poltava region temporarily cut power to consumers, which has since been restored, Governor Volodymyr Kohut said in a statement on the Telegram messaging app.
Significant parts of the northern city of Sumy were left without power, the energy ministry said.
All water utility facilities were relying on emergency backups as of this morning, said Serhii Kryvosheienko, the head of Sumy city military administration.
Healthcare facilities also used backup power sources, he added.
The Ukrainian Air Force said it had downed 74 drones out of 95 launched by Russia overnight, and that 21 drones had struck nine locations around the country.
Russia has denied targeting civilians since launching its full-scale invasion in February 2022 but says energy systems and other infrastructure are legitimate targets because they help Ukraine's war effort.
Accreditation: AFP/Reuters