The Kurdish regional government in northern Iraq says it has driven the Islamic State group out of more than 140 sq. kilometers (54 sq. miles) of territory near the oil-rich city of Kirkuk and cleared part of a major highway.

A statement from the Kurdistan Region Security Council on Wednesday said Kurdish peshmerga fighters backed by U.S.-led airstrikes pushed the militants beyond Ghara Heights and Mount Batiwa, south of Kirkuk, and secured a stretch of a highway which connects it to the central city of Samarra.

The IS group swept across northern Iraq in the summer of 2014 and currently holds roughly a third of Iraq and neighboring Syria. The Kurdish government says some militants were seen fleeing toward the contested town of Hawijah.