In Ukraine hundreds could be trapped under the rubble in a bombed theatre in the port city of Mariupol as Russian forces close in on Kyiv where residential blocks have been hit by isolated strikes for the past several days. The UN warns that humanitarian needs are becoming ever more urgent across eastern Ukraine, with a potentially fatal lack of food, water and medicines in besieged cities such as Mariupol and Sumy. More than 3.25 million refugees have fled Ukraine since the Russian invasion, the United Nations says, with more than two million crossing the Polish border.