Authorities in Mariupol have said as many as 300 people were killed in a Russian bombing of a theatre last week, putting a death toll for the first time on the deadliest single attack since Moscow launched its invasion of Ukraine more than a month ago.
The figure, based on the accounts of witnesses, came as the United Nations human rights team in Ukraine said it had reports of mass graves in the southern port city, including one that appeared to hold 200 people.
