More than three million people havefled Ukraine since Russia invaded on February 24, nearly half of them minors, with a child becoming a refugee every second, the UN said. “We have now reached the three-million mark in terms of movement of people out of Ukraine,” Paul Dillon, a spokesman for the United Nations migration agency (IOM), told reporters. Less than three weeks into the invasion, “three million lives uprooted. Three million women, children and vulnerable people separated from their loved ones,” IOM chief Antonio Vitorino said in a tweet. “We need an immediate cessation of hostilities…