For the second day in a row a US military convoy has come under attack near Fallujah. It is not yet clear if there are any casualties.

On Wednesday four U.S. contractors were murdered and then mutilated in the Iraqi city of Fallujah in one of the most graphic attacks on U.S. interests since the invasion of Iraq. And nearby five U.S. soldiers were killed in a separate attack.

In the attack on the contractors, news agencies captured photos and images of their burnt corpses being dismembered in the streets. Two of bodies were tied up under a bridge and lynched over the Euphates. The others were dragged through the streets behind cars and hacked to pieces.

The New York Times reports seeing a 10-year-old body stepping on a burnt head screaming “Where is Bush? Let him come here and see this!”

The incident came on the same day the total number of U.S. soldiers killed in Iraq reached 600.

The four Americans killed on Wednesday all worked for the firm Blackwater, which routinely hires former soldiers often ex-Navy Seals to form essentially a private army that largely exists outside the public eye.

It is unknown how many private U.S. contractors have been killed though it has been reported the Army is relying on private security companies more as the opposition to the occupation intensifies.

There appears to have been no US effort to save the contractors or even to collect the bodies until hours after the attack.

On Wednesday the Coalition Provisional Authority’s Web site didn’t even mention the attacks. One of the top headlines on the website read “Iraqi Police Equal to Task of Public Safety”

Middle East analyst Juan Cole says the degree of hatred among ordinary Iraqis toward Americans is bad news for the occupying forces.

He writes, “It helps explain why so few of the Sunni Arab guerrillas have been caught, since the locals hide and help them. It also seems a little unlikely that further US military action can do anything practical to put down this insurgency; most actions it could take would simply inflame the public against them all the more. It seems likely to me that the guerrilla violence will continue for years.”