KYIV/KHARKIV, Ukraine: Ukraine accused the Russian military of attacking civilian infrastructure in response to a rapid weekend offensive by Ukrainian troops that forced Russia to abandon its main bastion in the Kharkiv region.

Ukrainian officials say the attack destroyed Kharkiv's irrigation facilities and a thermal power plant, throwing the entire region into darkness.

"The attack is aimed at depriving people of access to light and heat," Ukrainian President Volodymyr Zelenskyy tweeted late Sunday.

Moscow denies that its forces deliberately target civilians.

Last weekend, the Ukrainian army launched a swift offensive in the country's northeast, driving out Russian troops. As a counterattack, Russia attacked many areas including the Ukrainian thermal power station on Sunday.

A power station on the western outskirts of Kharkiv was hit by fire as a result of the bombing. President Volodymyr Zelensky condemned Russia's deliberate and malicious missile attacks on civilians.

The Zaporizhzhia nuclear power plant in the Russian-held south was completely shut down in an attempt to prevent a radiation disaster after fighting intensified nearby.

Ukraine's military chief, Gen. Valery Salushny, said troops had retaken about 3,000 square kilometres (1,160 square miles) since the counteroffensive began in early September. He said Ukrainian forces were only 50 kilometres (about 30 miles) from the Russian border.

Ukrainian officials said Russia hit Kharkiv TEC-5, the country's second-biggest heat and power plant, and Zelenskyy posted a video of the Kharkiv power plant on fire.