BAGHDAD, 4 May 2007 — A senior Iraqi official said yesterday that the leader of an Al-Qaeda front group had been killed in a clash with Iraqi security forces north of Baghdad, but the US military said it could not confirm the report.

Maj. Gen. Hussein Kamal of the Interior Ministry said Abu Omar Al-Baghdadi was killed Wednesday night in a battle with security forces north of Baghdad.

Al-Baghdadi heads the Islamic State of Iraq, which includes Al-Qaeda and seven smaller groups.

Kamel said Al-Baghdadi’s body was in Iraqi custody and would undergo DNA testing.

It was the second time this week that the Iraqis have reported the alleged death of a major Al-Qaeda figure. The US military has urged caution in both cases.

“We’ll go back and take a look at it as we always do when these reports come out,” military spokesman Lt. Col. Christopher Garver said yesterday.

State-run Iraqiya television showed photos of a bloated body in a wooden box in the back of a pickup truck that it said was that of Al-Baghdadi, but that could not independently be confirmed.

Iraqi officials have released similar reports about the killing or capture of top insurgent figures, including Al-Baghdadi, only to acknowledge later that the claims were inaccurate. In March, the Iraqi military announced Al-Baghdadi had been captured in a raid west of Baghdad and had confessed to his identity.

The Iraqis later acknowledged the report was wrong.

On Tuesday, officials reported the leader of Al-Qaeda in Iraq, Abu Ayyub Al-Masri, had been killed by rivals north of Baghdad but the body has not been recovered.

Also, a rocket attack on Iraq’s heavily fortified Green Zone killed four Asian contractors working for the US government, the American Embassy said yesterday.

It was the third straight day that extremists used rockets or mortars to hit the area where Iraq’s Parliament meets.

The embassy said Wednesday’s attack left it “with a profound sense of sadness and regret” over the loss of Asians who “were integral members of our embassy community.”

The brief statement provided no other details about the attack, including the time or location of the explosion in the Green Zone, which is home to the US and British embassies and thousands of American troops.

Such information often is withheld to avoid giving extremists information for future attacks on the area.