People fleeing Mariupol, as well as other areas of Ukraine affect by fighting, arrive at a humanitarian centre in Zaporozhye to receive food and medical firstaid. UN figures show that nearly 3.7 million Ukrainians including 1.8 million children have fled abroad, and more are now displaced inside Ukraine after harrowing journeys out of cities like Mariupol. In the besieged southern port, Ukraine's President Zelensky says that nearly 100,000 people are trapped without food, water or power and enduring fierce shelling by Russian forces. IMAGES AND SOUNDBITES