Russian forces dropped a powerful bomb on a theatre in the encircled Ukrainian port city of Mariupol where hundreds of civilians were sheltering, Ukraine's foreign ministry said.
The ministry said many people were trapped in the theatre and accused Russia of committing a war crime.
It said the number of casualties was not yet known.
Reuters could not independently verify the information.
Another horrendous war crime in Mariupol. Massive Russian attack on the Drama Theater where hundreds of innocent civilians were hiding. The building is now fully ruined. Russians could not have not known this was a civilian shelter. Save Mariupol! Stop Russian war criminals! pic.twitter.com/bIQLxe7mli
— Dmytro Kuleba (@DmytroKuleba) March 16, 2022
Russia denies targeting civilians.
In Moscow, the defence ministry said its forces had not struck the building and instead accused the Azov Battalion, a far-right Ukrainian militia, of blowing it up, RIA news agency said.
It did not give evidence to back up the claim.
Russia had previously accused the battalion of preventing civilians from leaving the city, which has come under heavy bombardment.
Maxar Technologies, a private US company, distributed satellite imagery that it said was collected on Monday 14 March and showed the word "children" in large Russian script painted on the ground outside the red-roofed Mariupol Drama Theatre.
Maxar said it would distribute new images of the theatre as soon as it has them.
