before and after satellite images reveal extraordinary devastation. in commercial and shopping areas, residential neighborhoods too. russian munitions are steadily wiping out this city. it's already unlivable. there is no food, water, or power. ukraine's president, volodymyr zelenskyy, says a child in mariupol has died of dehydration, probably for the first time since the nazi invasion. during a meeting in turkey, the ukrainian foreign minister says he asked his russian counterpart for a humanitarian corridor to allow people to leave mariupol. >> unfortunately, minister lavrov was not in a position to commit himself to it, but he will correspond with respective authorities. >> reporter: that means sergey lavrov has to ask his boss. but russia's top diplomat was