Dozens of people have been killed in attacks in Iraq, with seven bombs exploding in Baghdad and attacks killing many in Mosul and Fallujah.

The attacks on Tuesday were the latest in a surge of unrest that has left more than 4,200 people dead this year.

The evening car bombings struck various parts of Baghdad, including Shia Muslim neighbourhoods in the centre and northeastern districts, killing at least 23 people, most of them civilians, and wounding 87, security and medical sources said.

Earlier in the day, a provincial official was also shot dead in Baghdad.

In the predominantly Sunni Muslim western city of Fallujah, three suicide bombers attacked a police station, killing at least eight people, police said.

Armed men also ambushed a minibus carrying soldiers and policemen on the way to join units in the northern city of Mosul, shooting dead at least six of them in a town 50km south of the city.

A separate attack west of Mosul left a soldier dead.

More than two years of civil war in neighbouring Syria have worsened deep-rooted sectarian divisions and shaken Iraq's fragile coalition of Shia, Kurdish and Sunni factions.

The Shia-led government has faced criticism for not doing more to defuse Sunni Arab anger over perceived ill-treatment.

Analysts and diplomats say fighters have exploited the minority community's disenchantment to recruit and carry out more attacks.

The surge in violence comes as the government grapples with a prolonged political stalemate, with no significant legislation passed since March 2010 parliamentary elections.

Source: Agencies