Up to a quarter of Iraq’s Christians are reported to be fleeing after Islamic militants seized the minority’s biggest town in the country, the BBC reported.
The Islamic State (IS) group captured Qaraqosh in Nineveh province overnight after the withdrawal of Kurdish forces.
Meanwhile, the UN says some of the 50,000 members of the Yazidi religious minority trapped by IS on Mount Sinjar have been rescued.
IS controls parts of Iraq and Syria and says it has created an Islamic state.
Nineveh, located 400km (250 miles) north-west of Baghdad, is home to a large number of religious minorities.
Tens of thousands have been forced to flee since IS, a Sunni Muslim group formerly known as Isis, launched their onslaught in the north in June.