Iraqi security forces on Tuesday fought fierce clashes against the Islamic State (IS) militants and made new gains in the battleground town of Heet in Iraq's western province of Anbar, a provincial security source told Xinhua.

Security forces and allied paramilitary Sunni tribal fighters continued their offensive campaign aiming to drive out the IS militants from the town of Heet, 160 km west of the Iraqi capital of Baghdad, the source said on condition of anonymity.

The troops, backed by the U.S.-led coalition aircraft, retook control of the districts of Zuhour, Qadsiyah and Shuhadaa in the western part of Heet after fierce house-to-house battle, leaving 35 IS militants killed and many of heir vehicles destroyed, the source said.

Eight security members were also killed and five others wounded in the battle, the source added.

In the last few days, troops have slowed their advance into the town of Heet in order to give thousands of civilians trapped in the town an opportunity to flee their homes.

The troops seized the government compound a week ago and raised the Iraqi flag on a main building after the IS militants withdrew from the downtown and eastern part of Heet, but clashes are still ongoing in order to flush out remaining IS militants from the town's western part.

Last December, the troops recovered Ramadi, the provincial capital of the country's largest province of Anbar.

Separately, an army officer and three soldiers were killed in a roadside bomb explosion near their patrol in Falahat area in west of the IS-held city of Fallujah, some 50 km west of Baghdad, the source said.

Iraqi security forces and allied Sunni paramilitary tribal units have been battling IS militants for re-control of large territories in northern and western Iraq that have been seized by the IS since June 2014.

Source: XINHUA