KYIV: About 300 people were killed in the Russian airstrike last week on a Mariupol theatre that was being used as a shelter, Ukrainian authorities said on Friday in what would make it the war’s deadliest known attack on civilians yet.

The bloodshed is certain to fuel allegations Moscow has committed war crimes by killing civilians, whether deliberately or by indiscriminate fire. For days, the government in the besieged and ruined port city was unable to give a casualty count for the March 16 bombardment of the grand, columned Mariupol Drama Theatre, where hundreds of people were taking cover, the word CHILDREN printed in Russian in huge white letters on the ground outside to ward off aerial attack