BAGHDAD, Aug. 3 (Xinhua) -- Twelve Islamic State (IS) militants were killed during an overnight operation to hunt down the extremist militants in Iraq's central province of Salahudin, a provincial security source said on Friday.

A joint force from Iraqi army, police and paramilitary Hashd Shaabi fighters launched an operation late on Thursday night designed to clear IS militants in Es'haqi area in southwest of the city of Samarra, some 120 km north of the Iraqi capital Baghdad, Sabir Ali Hussein from Samarra Operations Command told Xinhua.

Acting on intelligence reports, the troops attacked IS hideout in the area and killed 12 of the extremist militants, including four suicide bombers wearing explosive belts, Hussein said.

The security situation in Iraq has been dramatically improved after Iraqi security forces fully defeated the extremist IS militants across the country late in 2017.

However, small groups and individuals of extremist militants melted or regrouped in urban and rugged areas, and are carrying out attacks against the security forces and civilians despite operations from time to time to hunt them down.