Twelve Iraqis were killed and nine others wounded in an overnight US air raid on the Iraqi flashpoint city of Fallujah, medical sources and witnesses said on Thursday.

The casualties include several women and children, said doctors in the general hospital of the city.

Two houses were destroyed in the airs raid which took place at 2:00 a.m. (2200 GMT), the witnesses said, adding it was the third successive overnight air raid on the city.

The US marines have been fighting insurgents in the city for the third consecutive day.

The US military said in a statement that multinational forces had carried out a "precision strike" on a site allegedly used by supporters of Abu Musab al-Zarqawi.

Al-Zarqawi, a Jordanian militant who the Americans say is a key al-Qaida operative and the most wanted man in Iraq, who is accused of masterminding major attacks including suicide bombings.

"The target was a building frequently used by terrorists," the US military statement said, adding "three Zarqawi associates were reported to be in the area, no other individuals were present at the time of the strike."

On Tuesday, US warplanes fired a number of missiles into Fallujah after seven Marines were killed in a suicide car bombing on the outskirts of Fallujah Monday.