Sunni insurgents seized a mainly ethnic Turkmen city in northwestern Iraq on Sunday after heavy fighting, solidifying their grip on the north after a lightning offensive that threatens to dismember Iraq.
Residents reached by telephone in the city of Tal Afar said it had fallen to the rebels from the Islamic State of Iraq and the Levant after a battle which saw heavy casualties on both sides.
"The city was overrun by militants. Severe fighting took place, and many people were killed. Shi'ite families have fled to the west and Sunni families have fled to the east," said a city official who asked not to be identified.
Tal Afar is a short drive west from Mosul, the north's main city, which the ISIL fighters seized last week at the start of a drive that has plunged the country into the worst crisis since U.S. troops withdrew.
Most of the inhabitants of Tal Afar are members of the Turkmen ethnic group, who speak a Turkic language. Turkey has expressed concern about their security.
The city had been defended by an unit of Iraq's security forces commanded by a Shi'ite major general, Abu Walid, whose men were among the few holdouts from the government's forces in the province around Mosul not to flee the rapid ISIL advance.
After sweeping through towns in the Tigris valley north of Baghdad, ISIL fighters appear to have halted their advance outside the capital, instead moving to tighten their grip on the north.
The Turkmen and other residents of Tal Afar are divided among Sunnis and Shi'ites in a part of Iraq with a complex ethnic and sectarian mixture. The city is just outside Iraq's autonomous Kurdish region, whose own security forces have taken advantage of the collapse of government control to advance into the city of Kirkuk and rural areas with oil deposits.
ISIL fighters aim to establish a Caliphate on both sides of the Syria-Iraqi frontier based on strict medieval Sunni Muslim precepts. Their advance has been assisted by other Sunni Muslim armed groups.