Footage uploaded to social media today by the Amaq news agency which supports Islamic State, purports to show an Iraqi Air Force plane being shot down over Hawija, northwest of the oil city of Kirkuk.

Amaq also reported that five people on board had been killed.

The video showed a plane falling to the ground amid cheers from insurgents, while another clip showed the wreckage of what is said to be the Iraqi plane and human body parts scattered around it.

An Iraqi military spokesman confirmed an Iraqi Air Force plane crashed  near Kirkuk and its two pilots and a third member of the crew are missing.

The single turbo-propeller plane was on a 'reconnaissance and combat mission' over territory held by Islamic State militants in northern Iraq, the spokesman, Brigadier General Yahya Rasool, told Reuters.

An investigation is underway to determine whether the plane was shot down by militants or crashed because of a technical failure, he said.