Summary

1. A planned mass evacuation of civilians from Mariupol is aborted as Russia continues shelling the key southern city
2. Attacks are continuing, Ukrainian officials say, despite a ceasefire designed to allow thousands of people to leave
3. Civilians have also been unable to escape the nearby city of Volnovakha
4. Protests have broken out in Kherson - the only big city to have been captured by Russia so far
5. Meanwhile, Vladimir Putin has warned the West he would regard any no-fly zone over Ukraine as an act of war
6. Ukraine's president has condemned Nato for ruling out a no-fly zone. Western leaders say they don't want to make the situation worse