Baghdad: Iraqi militants from The Islamic State of Iraq and the Levant (Isil) 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 Thursday.

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

Isil 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 US 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 Isil militants with little apparent progress.

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

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 10pm, most Kurdish fighters had pulled out, said Father Gabriel, a resident of Al Qosh.

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, Isil 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 Isil intensified efforts to expand its territory.

On Monday, Prime Minister Nouri Al Maliki ordered the Iraqi air force to provide aerial support to the peshmerga, in a rare show of cooperation between Baghdad and the Kurdish regional government that underscored the serious nature of this crisis.

In Batella, one of the hamlets overrun overnight, Kurdish fighters and local Christian security guards went knocking on people’s doors, urging them to leave, said Um Fadi, who only gave her knickname, fearing for her own safety.

A government employee who fled from Mosul with her family for refuge in Batella more than two weeks ago, Um Fadi said she was in despair. “Our situation is miserable,” she told the AP by phone on Thursday. “We do not know what to do or where to go.”

The head of the Kurdish regional government, Nechirvan Barzani, urged Iraqi Kurds “not to panic but to remain calm,” stay where they are and continue their “normal work and life.”

Last week, Isil also seized the northwestern town of Sinjar, forcing tens of thousands of people from the ancient Yazidi minority to flee into the mountains and the Kurdish region.

Meanwhile, the death toll from a series of bombings in Baghdad on Wednesday rose to 61, after several of those wounded died. A pair of car bombs first exploded in the densely populated Shiite neighborhood of Sadr City, followed by another bomb in the nearby area of Ur and two more bombings in southeast Baghdad.

Also Thursday, the Iraqi parliament was to discuss candidates for the post of prime minister, a first step toward forming a new government. The discussion was postponed Tuesday after officials with al-Maliki’s State of Law bloc, which won the most votes in elections in April, or the larger coalition it is part of should nominate a candidate.

Al Maliki, a Shiite, has vowed to stand for a third four-year term as prime minister, but many of his critics have called for his removal, accusing him of monopolising power and alienating Sunni and Kurdish minorities.

Iraq badly needs a government if the country is to unite and confront the threat posed by Islamic State.