Iraqi PM promises to free 2,500 prisoners

His comments came a day after the abductions of 50 people in downtown Baghdad by gunmen wearing police uniforms and the shooting deaths of 21 Shias north of the capital, including students pulled from their minivans.

Prime Minister Nouri al-Maliki blamed a desire by insurgents to cripple the political process for the spike in violence since he took office just over two weeks ago.

They "have increased their bloody operations to derail and bring down the national unity government, but, God willing, they will lose," he told reporters.

Just after dawn Wednesday, a roadside bomb killed two police officers and wounded another two near a passport office in eastern Baghdad, police 1st. Lt. Ahmed Muhammad Ali said. Three rockets also killed a man and wounded his two brothers sleeping on their roof in Baladiyat, an eastern Baghdad neighbourhood. The target was unclear.

Late Tuesday, and just hours after al-Maliki spoke, a parked car bomb exploded outside a Shia funeral ceremony in southwestern Baghdad, killing at least four people and wounding 20. Gunmen also killed one student, wounded another and kidnapped three at Baghdad University's business school.

The US military, meanwhile, reported an American soldier was killed in Baghdad on Monday when a bomb struck his convoy.

Underlining the toll of Iraq's bloodshed, the Health Ministry said that during the first five months of this year, Baghdad's main morgue had received 6,000 bodies, most of whom had died violently.

In an apparent effort to appease anger in the Sunni Arab minority over allegations of random detentions and mistreatment of prisoners, al-Maliki said 2,500 Iraqi detainees would be freed from US and Iraqi-run jails to promote "reconciliation and national dialogue."

The first batch of about 500 detainees will be released Wednesday and others will follow after their cases are reviewed, he said.