safe, secure, and predictable lives to imagine what sergei and his family has gone through and may yet go through in the days and weeks ahead. a few weeks ago, it was hard for most ukrainians to believe it either. cnn chief international correspondent clarissa ward is in kyiv. jim sciutto is here in lviv, and cnn s nick paton walsh is in nick oev. first, an update from oren liebermann. in northeast ukraine, not far from the russian border, the city of sumi was supposed to be safe if only for a few hours. ukraine and russia agreed on a single evacuation corridor opened for half of tuesday, but the agreement has not protected the city. the announcement came after ukrainian officials say a russian air strike killed 21 civilians including two children overnight. russian strikes have destroyed homes in the city, flattening neighborhoods. western leaders have already accused russia of targeting preapproved safe routes in ukraine. the city of maria pole in the