A ceasefire to evacuate the city of Mariupol in southern Ukraine fails after minutes

is fuzzy and faint, but any phone connection at all after a communications blackout lasting days is a miracle in itself. Dmitry, a doctor trapped in the encircled city of Mariupol, is shouting what he can down the receiver, and not all of it gets through. The internet, like electricity and heating, is down all over the city, he says. Mariupol’s inhabitants are living underground, and in darkness. But his most pressing problem is finding enough diesel for the city's hospital to keep its generators running. Without it, operations and many other treatments will be impossible. Mariupol, a strategic port city on the Sea of Azov, has been preparing for a siege for years. It sits just within government-controlled territory, only a few miles from areas seized by Russian-backed separatists in 2014. The dreaded moment has now arrived. For four days there has been no way out. A Russian bombing campaign appears to have targeted civilian infrastructure and residential districts indiscriminately, using weapons with little precision: Grad missiles, artillery and even, the Ukrainians claim, cluster bombs. Food and water are thought to be running short, especially in the city’s relatively isolated western suburbs. “I don't know what the Russians want to do,” the city’s mayor, Vadim Boichenko, told Ukrainian journalists on March 4th. “Perhaps their aim is to wipe Mariupol from the face of the earth.”