A series of attacks including car bombings in Baghdad, an explosion at a market and a suicide assault in a northern city killed at least 66 people Sunday across Iraq, officials said, the latest in a wave of violence washing over the country.

Co-ordinated bombings hit Iraq multiple times each month, feeding a spike in bloodshed that has killed more than 5,000 people since April. The local branch of al-Qaeda often takes responsibility for the assaults, although there was no immediate claim for Sunday's blasts.

Sunday's attacks were the deadliest single-day series of assaults since Oct. 5, when 75 people were killed in violence.

Police officers said that the bombs in the capital, placed in parked cars and detonated over a half-hour period, targeted commercial areas and parking lots, killing 42 people.

The deadliest blasts struck in the southeastern Nahrwan district, where two car bombs exploded simultaneously, killing seven and wounding 15, authorities said. Two other explosions hit the northern Shaab and southern Abu Dashir neighbourhoods, each killing six people, officials said. Other blasts hit the neighbourhoods of Mashtal, Baladiyat and Ur in eastern Baghdad, the southwestern Bayaa district and the northern Sab al-Bor and Hurriyah districts.

Soldiers targeted

Iraq bombings

Citizens inspect the site of a car bomb attack at a bus station in the Baghdad's eastern Mashtal neighbourhood. (Khalid Mohammed/Associated Press)

Meanwhile, in the northern city of Mosul, a suicide bomber drove his explosives-laden car into a group of soldiers as they were sealing off a street leading to a bank where troops were receiving salaries, killing 14, a police officer said. At least 30 people were wounded, the officer said. Also in Mosul, police said gunmen shot dead two off-duty soldiers in a drive-by shooting.

The former insurgent stronghold of Mosul is located about 360 kilometres northwest of Baghdad.

In the afternoon, a bomb blast killed four people and wounded 11 inside an outdoor market in the Sunni town of Tarmiyah, 50 kilometres north of Baghdad, authorities said.

Sunday night, police said mortar shells landed on homes in a Shia district of Madain, a town just south of Baghdad, killing four people and wounding nine, officials said.

Such co-ordinated attacks are a favourite tactic of al-Qaeda's local branch. It frequently targets civilians in markets, cafes and commercial streets in Shia areas in an attempt to undermine confidence in the government, as well as members of the security forces. All of the car bombings Sunday in Baghdad struck Shiite neighbourhoods.

In Mashtal in Baghdad, police and army forces sealed off the scene as ambulances rushed to pick up the wounded. Pools of blood covered the pavement. The force of the explosion damaged number of cars and shops. At one restaurant, the blast overturned wooden benches and left broken eggs scattered on the ground. In Shaab, a crane lifted away at least 12 charred cars as cleaners swept away debris.

Medical officials confirmed the casualty figures for all attacks. All officials spoke on condition of anonymity as they were not authorized to publicly release the information.

Violence has spiked in Iraq since April, when the pace of killing reached levels unseen since 2008. Today's attacks bring the death toll across the country this month to 545, according to an Associated Press count.