Suicide bomber kills 11 in Iraq

Seventeen people have been killed and more than two dozen have been wounded in a day of bombings and shootings in Iraq.

A suicide bomber has detonated an explosives-rigged vehicle at an Iraqi checkpoint, killing 11. (AAP)

A suicide bomber has detonated an explosives-rigged vehicle at a checkpoint in Iraq, killing 11 people and sparking angry protests.

The latest bloodshed comes amid a protracted surge in nationwide violence that has claimed more than 2550 lives so far this year.

The suicide bomber attacked a police checkpoint in Dibs, in the country's north, killing seven police and four civilians, and wounding 18 people, among them security forces members.

Following the blast, an angry crowd torched a local courthouse and five homes, including those of a police colonel and a judge.

In a village in the Sulaiman Bek area, also north of Baghdad, gunmen attacked a police officer's house, killing his father and brother and wounding two more people.

The gunmen also shot dead a Sahwa anti-al-Qaeda militiaman nearby.

And a roadside bomb in the Dujail area, near the northern city of Tikrit, killed three people and wounded six.

Iraq's first general election since American troops left at the end of 2011 will be held on April 30, in a major test for the security forces.

While they were able to keep violence to a minimum during provincial polls last year, they have failed to halt a subsequent year-long surge in unrest.