The army, rapid intervention and paramilitary forces, in coordination with Kurdish fighters and with Iraqi and coalition air cover, launched the operation east of Tuz Khurmatu "to chase away IS remnants," Iraq's Security Information Centre said.

"Air strikes targeted the Hamrin mountain range, destroying 50 targets, including two fortified hideouts, 20 terrorist caches, weapons warehouses, ammunition as well as communication networks, mortar positions and 24 tunnels," it added.

Iraqi forces took control of 80 square kilometres (30 square miles), three oil wells and two gas fields, according to the rapid intervention forces.

They also retook five villages and stormed an IS camp.

Iraq declared victory against IS in December, more than three years after the extremist group seized a third of its territory and swathes of neighbouring Syria, declaring a "caliphate" ruling over millions of people.

The jihadists are still active, however, and there have been several attacks against government forces in the Khurmatu region.

Authorities have blamed not just IS but also pro-independence Kurds, who are accused of seeking revenge after government forces seized control of Kirkuk province, during which many Kurds were expelled from the Tuz Khurmatu area.

The town is home to a mix of Kurds, Arabs and Turkmens. It was the scene of deadly violence in mid-October when Iraqi forces retook it in response to a Kurdish independence referendum bitterly opposed by Baghdad.