Twenty-four people were killed and 16 others wounded in separate violent attacks across Iraq on Thursday, police said.

In Anbar province clashes erupted between Iraqi forces and gunmen near the provincial capital Ramadi, some 110 km west of Baghdad. Police said 11 gunmen were killed. They were believed to be linked to al-Qaida organizations.

Also in Ramadi gunmen attacked an army checkpoint, killing two soldiers and injuring five others.

Another similar clash about seven km west of Ramadi resulted in the killing of four gunmen.

In the south of the militant-seized city of Fallujah, some 50 km west of Baghdad, snipers shot dead a civilian who was driving his car.

Anbar province has been the scene of fierce clashes that flared up after Iraqi police dismantled an anti-government protest site outside Ramadi in late December last year.

In east Baghdad, a car bomb killed a civilian and wounded five others.

Also explosive experts carried out a controlled detonation to a car bomb in downtown Baghdad, without casualties.

In a separate incident, a roadside bomb struck a bus in northeast Baghdad, killing a passenger and wounding three others.

In addition, three soldiers were wounded when a roadside bomb exploded near their vehicle in Tarmiyah area, some 30 km north of Baghdad.

In Salahudin province, gunmen attacked a checkpoint manned by members of a government-backed Sahwa paramilitary group in the city of Shirqat, some 110 km north of the provincial capital Tikrit. Two group members were killed.

Salahudin is a Sunni-dominated province. Its capital Tikrit, some 170 km north of Baghdad, is the hometown of former Iraqi leader Saddam Hussein.

In Iraq's eastern province of Diyala, a police force found a body of an ex-officer of Saddam's army. He was kidnapped earlier near his house in the city of Maqdadiyah, some 100 km northeast of Baghdad. The body was riddled with bullets and dumped near a river outside the city.

Also in the province, unidentified gunmen shot dead a civilian in Maqdadiyah and fled the scene.

Iraq is witnessing its worst violence in recent years. The UN Assistance Mission for Iraq said a total of 8,868 Iraqis, including 7,818 civilians and civilian police personnel, were killed in 2013, the highest annual death toll in recent years.