U.N. says 2 million have fled the war as Ukraine accuses Russia of violating latest cease-fire for humanitarian evacuations

Reports on Tuesday from one of the Ukrainian cities hardest hit by Russia's seemingly indiscriminate artillery barrage suggested Russia might make good on its latest promise to allow civilians to flee. But even if the truce in the northeast city of Sumy holds and Russia keeps its promise to allow "humanitarian corridors" for evacuations from other cities, it will be a small saving grace in a tragedy that deepens by the hour.

The United Nations said Tuesday that more than 2 million people have fled from Ukraine into neighboring nations since Russia launched its brutal invasion 13 days ago. 

President Volodymyr Zelensky's office said Ukrainians would believe the Kremlin's offer to allow safe passage from Sumy, the capital Kyiv and the battered cities of Chernihiv, Kharkiv and Mariupol only when evacuations were underway. At least three previous localized cease-fires collapsed with Ukraine and Russia accusing each other of breaking the truces, and reports quickly emerged of fresh violations Tuesday in the southern port city of Mariupol.