The Iraqi Prime Minister Nouri al-Maliki vowed Saturday to eliminate "all terrorist groups" from Anbar province as a security source conceded the government had lost control of Fallujah to Al-Qaeda-linked fighters.

Maliki, speaking on state television, said his government would end "fitna," or disunity, in the province and would "not back down until we end all terrorist groups and save our people in Anbar."

The overrunning of Fallujah and Ramadi this week by the group Islamic State in Iraq and the Levant (ISIL) in the Sunni heartland of western Anbar provinces is a blow to the Shia-led government of Malik. His government has been struggling to contain discontent among the Sunni minority over Shia political domination that has flared into increased violence for the past year.

On Friday, ISIL gunmen sought to win over the population in Fallujah, one of the cities they swept into on Wednesday. A commander appeared among worshippers holding Friday prayers in the main city street, proclaiming that his fighters were there to defend Sunnis from the government, one resident said.

"We are your brothers from the Islamic State in Iraq and Levant," gunmen circulating through the city in a stolen police car proclaimed through a loudspeaker. "We are here to protect you from the government. We call on you to cooperate with us."

At least 40 of the ISIL fighters, who fought with machine guns and pick-up trucks mounted with anti-aircraft guns, were killed this week in Ramadi, medical and tribal sources told Reuters. There was no casualty figure for tribesmen or security forces. On Friday, two policemen were killed and six other wounded when their patrol was attacked by gunmen in speeding cars outside Fallujah, a police officer and a medical officials said.