In Washington, State Department spokesman Sean McCormack echoed Bergner's charges, saying they were "another data point in what is a troubling picture of Iranian negative involvement in Iraq."

"We have found that the Iranian Revolutionary Guard has essentially subcontracted out to some elements of Hezbollah, using them as a pass through for material, technology and other material assistance," McCormack said. "It is of deep concern to us."

Ray Takeyh, a senior fellow at the Council on Foreign Relations, said the allegations about Hezbollah were not surprising.

"Iran has always worked through Hezbollah, and it makes sense because Hezbollah is well-versed in this kind of terrain ... in this kind of ambiguous situation where there is sectarian violence and an outside occupation," said Takeyh.

An American soldier was killed Monday by an explosion in Salahuddin province, a center for Sunni insurgents northwest of Baghdad. The US military also reported the deaths of five US service members killed in fighting a day earlier, in attacks in Baghdad and western Anbar province.

But violence appeared sharply down in Baghdad and other parts of the country, amid an intensified US security sweep aimed at uprooting Sunni insurgents and Shiite militias in the capital and areas to the northeast and south.

Iraqi police reported four civilians killed in separate attacks in Baghdad. And car bomb hit the Baghdad district of Binouk in the evening, killing seven people and wounding 33, hospital officials said.

US warplanes struck buildings in the mostly Shiite city of Diwaniyah with 500-pound bombs early Monday, targeting sites suspected as the source of mortar fire, the US Air Force said. Iraqi police in the city said the raid killed 10 civilians, including women and children, wounded 25 others and damaged six homes. The police spoke on condition of anonymity because they were not authorized to release the information.

AP Television News footage from the area showed houses with large holes, as residents dug through rubble, pulling out at least one person on a stretcher. Following the raid, residents protested in the streets, and Iraqi police fired in the air to disperse them, killing one person. Some protesters fired back, wounding two policemen, a police officer said, speaking on condition of anonymity because he was not authorized to talk to the press.

1

2