The United Nations says at least 150,000 people have fled their homes in Yemen as renewed fighting, which has killed hundreds, spreads along the country's western coast. The Iran-backed Houthi rebels have advanced rapidly toward the Bab el-Mandeb Strait (a narrow, strategically vital waterway at the mouth of the Red Sea), clashing with Saudi-backed government forces and taking the city of Hays. Aid groups say many of those displaced have lost documents and belongings and that insecure areas are hard to reach, adding to a crisis in which more than 5.2 million Yemenis were already internally displaced after over a decade of conflict.