UNITED NATIONS (AP) — The United Nations humanitarian chief calls the crisis in Ethiopia a “stain on our conscience” as children and others starve to death in the Tigray region under what the U.N. calls a de facto government blockade of food, medical supplies and fuel. In an interview with The Associated Press, Martin Griffiths issued one of the most sharply worded criticisms yet of the world’s worst hunger crisis in a decade after nearly a year of war. He said memories of Ethiopia’s 1980s famine, whose images shocked the world, are vivid in his mind, “and we fervently hope is not happening at present.”