Suicide bombers killed more than 100 people in a Shi'ite neighbourhood of Baghdad and in a mainly Shi'ite town north of the Iraqi capital in a wave of sectarian violence today.
A suicide bomber killed around 60 people in a market in the Shaab district of northern Baghdad, police sources said.
Two police sources put the death toll at 60, with dozens more wounded, and said the blast was caused by a suicide bomber wearing an explosive vest.
A policeman at the scene of the blast in Baghdad
A Reuters photographer who went to a hospital in the area said doctors there put the death toll at 65 with many more wounded.
One of the wounded Wissam Hashim Ali (27), who was shopping at the market, believed the two car bombs had detonated.
"I saw heads separated from the bodies and legs blown off," he said.
"It was a very, very crowded market. All those killed are innocent,"
Shaab is very close to Sadr City, a Shi'ite militia stronghold in northeast Baghdad that has frequently been targeted by major car bombs blamed by the government on al Qaeda and other Sunni Arab insurgents.
At about the same time, three suicide car bombs exploded within minutes of each other in Khalis, 60 miles north of Baghdad, killing about 50 people and wounding around a hundred, police and hospital officials said.
One of the bombs exploded in a commercial area and a second at a police checkpoint leading to the police headquarters and court building. A third bomber attacked police patrols rushing to the scene.
"It was a scene of horror. There were charred bodies and human remains scattered about," said one policeman who spoke on condition of anonymity. Up to 48 people had been killed in the blasts, he added.
A second police source said more than 50 had been killed and more than 100 wounded.
There has been a spate of bombings outside Baghdad in recent weeks as US and Iraqi security forces launched a major crackdown on insurgents in the capital.
Iraq's Sunni Vice President Tareq al-Hashemi urged the government today to do more to purge security forces of militias after a group of Shi'ite police shot 70 Sunni men after two truck bombs in Tal Afar, near the Syrian border, killed 85.
Tal Afar was highlighted last year by US President George W Bush as an example of progress towards peace.
The governor of Nineveh province, which includes the town of Tal Afar, said policemen who took part in the reprisals were arrested but freed to prevent unrest.
Prime Minister Nuri al-Maliki, a Shi'ite, has ordered an inquiry into the involvement of police in the killings.
Mr al-Hashemi said militias acting under "official cover" should be treated as severely as insurgents.
Militia infiltration of security forces has long been a problem in restoring stability to Iraq, with many Sunnis complaining they are unfairly targeted by police and army.
New US ambassador Ryan Crocker told his swearing-in ceremony today that "terrorists, insurgents and militias continue to threaten security in Baghdad and around the country" and called Iraq the US's "most critical foreign policy challenge".