Iraqi government forces say they have taken control of more disputed areas previously held by Kurdish forces, the BBC reports.
Earlier this week, soldiers, police and special forces took control of the city of Kirkuk and nearby oilfields.
The operation came weeks after the Kurds held an independence referendum.
Voters in the autonomous Kurdistan Region overwhelmingly backed secession, but the vote was declared illegal by the Arab-led central government in Baghdad.
Iraqi Prime Minister Haider al-Abadi subsequently ordered troops to take control of all areas claimed by both his government and the Kurdish authorities.