Five security members were killed and three others wounded Sunday in an attack by Islamic State (IS) militants in Iraq's western province of Anbar, a provincial police source said.

The incident occurred when IS militants attacked a joint patrol of Iraqi army and Sunni tribal fighters with rockets on a desert road west of the provincial capital Ramadi, some 110 km west of Baghdad, Captain Ahmed al-Essawi told Xinhua.

The attack destroyed two military vehicles, he said, adding that the killed were three soldiers and two tribal fighters.

On June 30, Iraqi Prime Minister Haider al-Abadi, also the commander-in-chief of Iraqi forces, pledged to hunt down IS militants across Iraq after recent attacks and abductions carried out by the terrorist group.

"We will chase the remaining cells of terrorists in their hideouts. We will kill them, and we will chase them everywhere, in the mountains and the desert," Abadi said.

On Dec. 9, 2017, Abadi officially declared full liberation of Iraq from the IS. However, small groups of IS militants have since regrouped in rugged areas, carrying out attacks against security forces and civilians from time to time.