UN Secretary-General António Guterres strongly condemned the attack, which also damaged homes and critical civilian infrastructure, including health and educational facilities.

"Today's appalling attack – one of the deadliest against civilians since Russia's full-scale invasion nearly four years ago – once again underlines the urgency of a full, immediate and unconditional ceasefire in this country, as a first step towards a just, comprehensive, and sustainable peace,” his Spokesman, Stéphane Dujarric, told journalists in New York.

The UN Humanitarian in Ukraine, Matthias Schmale, issued a statement expressing his condemnation.

“From Kharkiv in the east to Ternopil and the Ivano-Frankivsk Region in the west, families have lost loved ones, suffered injuries and seen their homes destroyed,” he said.

At least a dozen children were among the wounded and “their suffering is unconscionable,” he added.

Political affairs chief ‘appalled’

UN human rights investigators are visiting the impacted sites to document the damage, according to a post on the social media platform X.

The UN Under-Secretary-General for Political and Peacebuilding Affairs, Rosemary DiCarlo, who is currently in Ukraine, said she was “appalled” by the overnight assault.

“Attacks against civilians and civilian infrastructure violate international humanitarian law. They are unacceptable and must end immediately,” she tweeted.

Damage and disruption

The barrage of drones and missiles also damaged energy infrastructure, causing emergency power outages and worsening the effects of previous attacks.

Mr. Schmale warned that the disruptions are putting millions “at grave risk” as temperatures drop below zero in some areas of the country.

“This relentless harm to civilians and destruction of essential civilian infrastructure is unacceptable,” he said, recalling that “international humanitarian law clearly prohibits attacks on civilians and civilian objects vital for their survival.”

He stressed that all measures should be taken to protect civilians and “they should never be a target.”