let's turn to the city of mariupol. it's a key port in southern ukraine. russia has been trying to take it for weeks. in the last few minutes a kremlin spokesman said the aim is clean out what it calls "nationalist units". the city is beseiged — and there's no power or clean water, and little food. ukrainian authorities say russian shelling has stopped rescue workers reaching this theatre in mariupol — which was targeted in an earlier attack. some people have managed to escape the city. let's hear from one of them. on the entrance to one of the checking points, ukrainian taking points, the russian started to shoot the cars with white ribbons on the doors with inscriptions of children on the windows and the heat actually one—car, seven or eight cars from me. my carjumped, actually, they