TIKRIT, Iraq, April 18 (Xinhua) -- Iraqi security forces Wednesday launched an operation to hunt down remnants of Islamic State (IS) militants, in mountainous area in Iraq's central province of Salahudin, a provincial security source said.

A joint force from the Iraqi army, police and paramilitary Hashd Shaabi brigades advanced in the morning to Makhoul mountain range and nearby Khanouqah hills in the northern part of Salahudin province to chase IS militants who repeatedly carried out attacks against civilians and Iraqi security forces in the area, Colonel Mohammed Khalaf from Salahudin provincial police told Xinhua.

The troops, backed by helicopter gunships and artillery, cleared large areas and pounded suspected hideouts of IS militants, Khalaf said.

The troops found four bodies of the extremist militants and seized caches of weapons and ammunition, including explosive belts and other equipment, Khalaf added.

Khalaf also said that a soldier was killed in a roadside bomb explosion while operating in Khanouqah hills.

The operation came six days after bomb attacks by IS militants on mourners at the cemetery of Sdeira al-Suflah, a village in east of the town of Shirqat, some 280 km north of the Iraqi capital Baghdad, which killed 10 mourners and wounded 14 others.

The mourners were gathering at the cemetery to bury four villagers who were also killed earlier by IS bomb attacks.

The attacks came despite repeated operations by Iraqi security forces to clear the areas around Shirqat of the remnants of IS militants.

During the past few months, dozens of IS militants fled their former urban strongholds in Mosul, Salahudin province and Hawijah area in the west of Kirkuk after the Iraqi forces cleared these areas through major anti-IS offensives.

However, many IS remnants have resorted to hideouts in mountainous and rugged areas near the rivers of Tigris and Zab, as well as Himreen mountain range that extends to neighboring Diyala province in eastern Iraq.

On Dec. 9, 2017, Iraqi Prime Minister Haider al-Abadi officially declared full liberation of Iraq from IS militants. But small groups of IS militants regrouped in the rugged areas and have been carrying out attacks against the security forces and civilians despite the repeated Iraqi military operations to hunt them down.