Russia targeted Ukraine's electrical power infrastructure, including the country's largest hydroelectric plant, in air strikes that killed at least five people and left more than a million people without power, according to reports.

The attacks Friday were the largest on Ukraine's energy utilities this year and one of the largest since Russia invaded in February 2022, the Associated Press.

"Even last winter, attacks on our energy system were not as large as they were this night," the head of energy utility Ukrenergo, Volodymyr Kudrytskyi, told the wire service.

Last winter, Russia's military regularly bombed the power grid, forcing millions to go without electricity, water and heat in what some Ukrainians believed was a concerted campaign to terrorize civilians.

Ukraine President Volodymyr Zelenskyy said about 60 drones and 90 missiles were used in the attack.

Zelenskyy, who has pleaded with the United States and its Western allies to bolster its air defense systems, said widespread assaults from Russia further depletes Ukraine's ability to fight back.

"With Russian missiles, there are no delays, like with aid packages to our state. Shaheds don't have indecisiveness, as do some politicians. It is important to understand the cost of delays and postponed decisions," Zelenskyy said, the AP reported, referring to the Iranian-made Shahed drones that Russia deploys.

About 1.2 million people in four areas of Ukraine were without power because of the attacks, according to totals that presidential aide Oleksy Kuleba posted on social media, with the bulk of the outages in the Kharkiv region, Reuters reported.

"The goal is not just to damage, but to try again, like last year, to cause a large-scale failure of the country's energy system," Energy Minister German Galushchenko said.