Civilians with small children in their arms and lugging heavy suitcases fled Monday from Ukraine's eastern city of Pokrovsk, where the Russian army was bearing down fast despite a lightning Ukrainian incursion into Russia's Kursk region.

Local authorities said Russian forces were advancing so quickly that families were under orders to leave the city and other nearby towns and villages starting Tuesday. Around 53,000 people still live in Pokrovsk, officials said, and some of them decided to get out immediately.