U.N. says tens of thousands flee IS assault in Northern Iraq

GENEVA (Reuters) - Tens of thousands of people have fled an assault by Islamic State on the town of Sinjar in northern Iraq on Sunday and are now surrounded, the United Nations said on Monday.

Islamic State inflicted a severe defeat on Iraq's Kurds on Sunday, when it made a rapid advance through three towns to reach the Mosul Dam, the largest in Iraq and a major source of electricity.