0ur correspondentjonah fisher is in lviv, the city in the west of ukraine which is serving as a hub for many of the people trying to flee the fighting. i asked him if he had any more details about the attack on the theatre in the besieged eastern city of mariupol, where hundreds of children were taking shelter. possibly a glimmer of what might turn out to be good news from mariupol. mariupol has been effectively cut off for the last two weeks. it has been encircled by russian troops so it's been very hard to get information in and out of the city. but we have had an mp from mariupol who has been speaking to the bbc in the last 20 minutes and if ijust read to you what he said. he said, "minutes ago we had information that the bomb shelter "survived and people there survived. "we don't yet know whether we have wounded people or killed people, "but it looks like most of them have survived and are ok." so, that is suggesting that when this bomb fell