Iraqi forces on Friday took control of the last district in the oil-rich province of Kirkuk still in the hands of Kurdish Peshmerga fighters following a three-hour battle, security sources said.
The district of Altun Kupri, or Perde in Kurdish, lies on the road between the city of Kirkuk—which fell to Iraqi forces on Monday—and Erbil, capital of the semi-autonomous region of Kurdistan in northern Iraq that voted in a referendum last month to secede from Iraq against Baghdad's wishes.
A force made up of US-trained Iraqi Counter-Terrorism Service units, Federal Police and Iranian-backed fighters known as Popular Mobilization began their advance on Altun Kupri at 7:30 am (0430 GMT), said an Iraqi military spokesman.
Kurdish Peshmerga forces withdrew from the town, located on the Zab River, after battling the advancing Iraqi troops with machine guns, mortars and rocket-propelled grenades, Iraqi security sources said. Neither side gave information about casualties.
"This is the beginning of the war between the Kurds and Baghdad," Goran Iz Al-Din, a Peshmerga commander, told CNN.
"We don't want to be ruled by Iran," he added, a reference to the fact that some of Iraq's Shiite militias—known as Popular Mobilization Units—are backed by Tehran.
The Iraqi central government forces have advanced into Kirkuk province largely unopposed as most Peshmerga forces withdrew without a fight.
The government advance has transformed the balance of power in northern Iraq and is likely to scuttle the independence aspirations of the Kurds, who voted overwhelmingly on Sept. 25 to secede from Iraq and take the oil fields of Kirkuk with them.
The fighting at Altun Kupri marked only the second instance of significant violent resistance by the Kurds in Kirkuk province. Dozens were killed or wounded in the previous clash on Monday, the first night of the government advance.
The US State Department on Friday urged the Baghdad government to avoid clashes in northern Iraq by limiting the movement of federal troops in disputed areas to those coordinated with the Kurdistan Regional Government.
In a statement, it said Washington was concerned by reports of violent clashes around Altun Kupri. "The reassertion of federal authority over disputed areas in no way changes their status. They remain disputed until their status is resolved in accordance with the Iraqi constitution," it said.