The death toll from an air strike on the village of Hroza in northeastern Ukraine has risen to 52, with rescue workers scouring the rubble for more bodies after what Ukrainian officials say is one of Russia’s deadliest attacks on civilians.

The latest victim died overnight in hospital, the regional governor said, following an attack in which a missile slammed into a cafe and grocery store on Thursday as people gathered to mourn a fallen Ukrainian soldier.

“Fifty-two people died as a result of this missile attack. One person died in a medical facility,” Oleh Synehubov, governor of the Kharkiv region, told Ukrainian television.

“People are still there (in hospitals). The injuries are quite serious.”

United Nations Secretary-General Antonio Guterres has condemned the strike on Hroza.

A three-day mourning period was announced in the wider Kharkiv region as villagers cleared grave sites for their relatives and rescuers continued their work at the scene, looking for body parts among piles of bricks, wood and metal.

The Kremlin reiterated on Friday that it does not attack civilian targets, distancing itself from a strike that resulted in one of the biggest civilian death tolls of the more than 19-month-old war.

Anguish amid burials

“It would have been better if I had died,” Valeriy Kozyr said as he prepared to bury his daughter and her husband, who were killed in Thursday’s attack.

“Oh God, you cannot punish me like this. To leave the father and take the children!”

Police investigators said that authorities would have to use DNA to identify some of the victims because their remains were beyond recognition.

“Corpses lay there in that yard, and nobody could identify them,” said Valentyna Kozienko, 73, speaking near her home close to the site.

United Nations Secretary-General Antonio Guterres condemned the missile strike, a UN representative said on Thursday, noting that “attacks against civilians and civilian infrastructure are prohibited under international humanitarian law”.

UN launches probe

On Friday, the United Nations High Commissioner for Human Rights deployed a field team to speak to survivors and gather information, OHCHR spokeswoman Elizabeth Throssell  said.

“The UN High Commissioner for Human Rights, Volker Turk, who saw for himself the horrific impact of such strikes, is profoundly shocked and condemns these killings,” she said.

OCHR said it was likely that the missile was fired by Russia but that it was too early to say for certain.

“At this stage, it’s obviously very difficult to establish with absolute certainty what happened,” Throssell  said.

“But given the location, given the fact that the cafe was struck and the indications are that it was a Russian missile.”

Kremlin spokesman Dmitry Peskov said Russia strikes military infrastructure, troop concentrations and the military leadership but not civilian targets.

However, many civilians have been killed in attacks that have hit residential areas as well as energy, defence, port, grain and other facilities.

In the latest air strikes early on Friday, missiles hit the city of Kharkiv in the northeast and grain and port facilities were damaged in the Odesa region in the south, Ukrainian officials said.

—AAP