Ukraine's president has condemned a Russian strike that the region's governor said killed at least six people and wounded 16 in Ukraine's Kharkiv on Wednesday as "despicable and cynical".
President Volodymyr Zelensky said a block of flats was "totally destroyed" in the attack, which he said "had no justification and shows the powerlessness of the aggressor".
"We will not forgive, we will take revenge", the president said on the Telegram app.
The strike started a fire in a block of flats in the northeastern city, mayor Igor Terekhov said on Telegram.
He earlier gave a toll of three dead and ten wounded, but regional governor Oleg Synegubov said the numbers had risen.
"Unfortunately the number of deaths and injuries following the bombardment... has increased: six people died and 16 were wounded," Synegubov said on Telegram.
Kharkiv was besieged in the first days of the invasion in February.
But Russian troops -- backed by massive artillery fire and missile strikes -- have not been able to take control of Ukraine's second city.
Hundreds of people have been killed in the region, authorities say.
On Monday, Russian shelling in the city killed at least one person and injured six more, senior police official Sergiy Bolvinov said on Facebook.
The bulk of Russia's offensive is now focussed on southern and eastern Ukraine.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)