Explosions in Iraq have killed at least 11 people and wounded 19 others - all civilians, police said.

One of the deadly blasts on Thursday targeted an Iraqi army patrol in al-Amariyah, a middle-class neighbourhood in west Baghdad, killing nine civilians and wounding six, according to Major Falah al-Mohammedawi of the Interior Ministry.

At Yarmouk hospital in west Baghdad, a car bomb was detonated, killing at least two people and wounding 13 as they entered the clinic, according to police Lieutenant Thaer Mahmoud.

The US military confirmed that a mass abduction from a security firm was the work of kidnappers masquerading as Interior Ministry commandos.

In an audacious attack on a locally owned security firm on Wednesday, attackers dressed as commandos stormed into the company's east Baghdad headquarters and took away 50 people, many of them ex-military personnel from the Iraqi army, which was disbanded by the former US administrator of Iraq, Paul Bremer.

"We can confirm based on our investigation that individuals dressed like this, in chocolate-chip desert combat uniforms, riding in eight vehicles, drove up and kidnapped 50 local nationals," US military spokesman Major-General Rick Lynch said on Thursday, referring to his combat fatigues.

"We don't know who did that. In our conversations with Iraqi authorities, they do not know either."

Security guards

The al-Rawafid Security Company was attacked by armed men who arrived in a convoy of vehicles, including several white 4WDs and a pickup mounted with a heavy gun that they used to carry away the hostages, said al-Mohammedawi.

The victims did not resist because they believed their abductors were police special forces working for the Interior Ministry, he said. "It was a terrorist act," said Major-General Ahmed al-Khefaji, an Interior Minister undersecretary.

Al-Rawafid headquarters is in Zayouna, a volatile and mixed Sunni-Shia neighbourhood in east Baghdad. One of its main clients is Iraqna, a cell phone company owned by Egyptian telecom company Orascom.

Iraqi Sunni Arabs have complained that they are under attack from death squads associated with the Interior Ministry, which is led by a politician of the Shia Alliance. The minister denies any involvement in sectarian kidnappings and killings.

Nevertheless, over the past two weeks - since the bombing of a Muslim shrine in Samarra - violence has become increasingly sectarian. Hundreds have been killed.

Lynch said that the US military believed at least 452 civilians had died in that violence through the first of this week, although he offered no breakdown according to religious sect or ethnicity.

Several blasts

Several other large blasts were heard in the capital on Thursday, but police only had details about one - a roadside bomb aimed at a police patrol in al-Jihad, a mostly Sunni western neighbourhood. Three bystanders were hurt.

The US military reported the death of another marine, killed on Wednesday in the Anbar governorate, the home of several Sunni groups opposed to US military presence in Iraq.

A day earlier, the Americans reported the deaths of a US soldier in the northern city of Tal Afar and of another marine, also in Anbar.

The three fatalities raised to at least 2304 the number of US service members who have died since the beginning of the war in March 2003, according to an Associated Press count. The figure includes seven military civilians.

Also on Thursday, a woman accountant was gunned down as she left her west Baghdad home for work, said police Lieutenant Mohammed Khayoun, who said she was attacked because she worked in the capital's American-controlled Green Zone.

PHOTO CAPTION

Iraqi army soldiers inspect the wreckage of car after a roadside bomb exploded, in Baghdad, Iraq, Thursday, March 9, 2006. (AP)