The Peshmerga have been fighting the Sunni militants in the north for weeks, and have been stretched thin across several fronts in Iraq, residents told AFP.
Some 50,000 Christians lived in the town of Qaraqosh, which lies 19 miles to the south east of the city of Mosul, which Isis captured in June and is now its main base in the country.
The BBC reports that the French organisation Fraternite en Irak said that a majority of inhabitants of Nineveh province had fled as the militants took over Qaraqosh.
The French group said the commander of the Peshmerga in Qaraqosh told the town’s archbishop late on Wednesday that the Kurdish fighters would be leaving their posts, while they also retreated from nearby Christian towns including Tel Eskof and Qaramless.
"I now know that the towns of Qaraqosh, Tal Kayf, Bartella and Karamlesh have been emptied of their original population and are now under the control of the militants," Joseph Thomas, the Chaldean archbishop of Kirkuk and Sulamaniyah, told AFP.
“It’s a catastrophe, a tragic situation. We call on the UN security council to immediately intervene. Tens of thousands of terrified people are being displaced as we speak, it cannot be described,” he said.
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