An Iraqi retrieves items from a destroyed shop the morning after a string of car bombs tore through busy shopping streets in several neighborhoods in Baghdad, Iraq, Thursday, Aug. 7, 2014. At least 50 people were killed on Wednesday as the army announced that one of its airstrikes had killed tens of militants in the northern city of Mosul.

BAGHDAD — Iraqi militants from the Islamic State group overran a cluster of predominantly Christian villages alongside the country’s semi-autonomous Kurdish region, sending tens of thousands of civilians and Kurdish fighters fleeing from the area, several priests in northern Iraq said today.

The capture of Qaraqoush, Iraq’s biggest Christian village, and at least four other nearby hamlets, brings the Islamic State to the very edge of the Iraqi Kurdish territory and its regional capital, Irbil.

The Islamic State has already seized large chunks of northern and western Iraq in a blitz offensive in June, including Iraq’s second-largest city of Mosul. The onslaught has pushed Iraq into its worst crisis since the 2011 withdrawal of U.S. troops.

The al-Qaida-breakaway group since has imposed a self-styled caliphate in territory it controls in Iraq and Syria, imposing its own harsh interpretation of Islamic law. Iraqi government forces and allied Sunni tribal militiamen have been struggling to dislodge the Islamic State militants with little apparent progress.

Bishop Joseph Tomas, who is based in the Kurdish-held city of Kirkuk, said the Islamic State pushed into Qaraqoush and four surrounding hamlets — Tilkaif, Bartella, Karamless and Alqosh — on Wednesday was in control of them today.

Kurdish peshmerga units, which had protected the area, fled along with civilians, Tomas said. Other priests contacted by The Associated Press confirmed the information.

The raid started late Wednesday, and by 10 p.m., most Kurdish fighters had pulled out, said Father Gabriel, a resident of Alqosh.

The Christians and members of other minority groups ran for their lives, with tens of thousands heading to Kurdish northern Iraq, he added.

“All Christian villages are now empty,” said Bishop Tomas.

When Mosul fell into the militant hands, the Islamic State gave members of the many ethnic and religious minorities an ultimatum to convert, pay a tax or leave. Those who did not obey risked death.

The peshmerga units had initially managed to stall the militant advances, but their defense waned in recent weeks as the Islamic State group intensified efforts to expand its territory.