Baghdad: At least 52 Islamic State (IS) militants were killed on Monday in separate clashes and US-led coalition air strikes in Iraq, security sources said.

In Iraq's western province of Anbar, hundreds of soldiers, police officers, Shia and Sunni militias launched an operation in the militant-seized town of al-Baghdadi, some 200 km northwest of the Iraqi capital Baghdad.

They retook control of part of the town, including its main police headquarters, after heavy clashes with the IS militants, Xinhua cited a provincial security source as saying.

The clashes left more than 20 militants killed, the source said without giving details about the casualties of the security members.

The security forces repelled an IS attack on a neighbourhood adjacent to al-Baghdadi, which was the scene of fierce clashes two days ago, leaving at least four IS fighters killed, including two suicide bombers, the source added.

On Saturday, the security forces broke the siege of the neighbourhood which is housing some 1,000 families of security personnel and government-backed Sahwa paramilitary group members. They have been trapped for about 10 days and the families have suffered from acute shortage in food and drinking water.

Separately, US and partner-nation warplanes conducted air strikes on IS positions near a bridge outside the militant-seized city of Fallujah, some 50 km west of Baghdad, killing at least five militants and wounding seven others.

Elsewhere, warplanes of the US-led coalition on late Sunday night hit an IS convoy outside a village near the town of Daqouq, some 40 km south of Iraq's northern city of Kirkuk, destroying two vehicles and killing some 18 militants aboard, a security source said.

In Iraq's northern central province of Salahudin, heavy clashes erupted near the town of Is'haqi, some 90 km north of Baghdad, between the security forces and dozens of IS militants who attacked a military base, leaving at least five extremist militants killed.

The security situation in Iraq has drastically deteriorated since June 10 last year, when bloody clashes broke out between Iraqi security forces and the IS, an Al Qaeda offshoot.

The IS has taken control of the country's northern province of Nineveh, and then seized swathes of territories after Iraqi security forces abandoned their posts in other predominantly Sunni provinces.