At least 73 people were killed on Friday in a Sunni mosque in Baquba in eastern Iraq, but accounts differ over who carried out the attack.

Some media have said the gunmen were from a Shia militia, possibly retaliating for a roadside bombing of one of their recruitment events.

However, other outlet point to the Islamic State, who have been fighting Iraqi forces near Baquba since the jihadists rapidly advanced from northern Iraq in June.

Graphic video captured the aftermath of the attack, with witnesses wailing over bodies of victims:

With the incident raising the prospect of the sectarian war from 2006 that killed tens of thousands of Iraqis, Prime Minister-designate Haider al-Abadi said, “I strongly condemn the killing of civilians and worshipers in Diyala province and I call on the citizens to reject these attempts by the enemies of Iraq to exploit the incident in order to stir up strife between the sons of the same homeland.”