HADITHA, Iraq – More than 1,000 American troops swept into this city yesterday on the road to Syria to root out insurgents – including those loyal to terrorist mastermind Abu Musab al-Zarqawi – after rebels damaged the hospital, knocked out the electricity, and prevented police from entering.

The American troops killed at least 10 suspected militants in Haditha, a Euphrates River city of 90,000 people – one of whom told the Marines that insurgents had recently killed her husband.

Speaking inside her home through a military interpreter, the woman moved her finger across her throat as she begged that her name not be used, indicating she could be killed for talking to American forces. She later helped cook a breakfast of eggs and bread for the handful of Iraqi soldiers helping guard the street.

“People have always been nice to us. But you can tell the [insurgents] have been doing some damage because people are real scared,” a platoon commander in the 3rd Battalion, 25th Regiment, Marine Captain Christopher Toland, said. The commander of the Haditha operation, Marine Colonel Stephen Davis, told CNN that Mr. al-Zarqawi “clearly is an influence out here. There are clearly links to him and to his elements out here in western Iraq.”

Yesterday’s offensive, the second on a road to Damascus in less than a month, came as the Iraqi government demanded that Syria block insurgents from crossing the border. Iraq also asked the U.N. Security Council to renew its mandate for the 160,000 troops in the American-led multinational force, saying it cannot fully defend itself alone.

Iraq wants the mandate to continue until the political transition is completed with elections under a new constitution “or until Iraq can provide for its security needs on its own,” Foreign Minister Hoshyar Zebari said in a letter which circulated yesterday.

Mr. Zebari is expected to attend a council meeting next week to review the mandate of the force, which has about 138,000 U.S. troops and more than 22,000 soldiers from 26 other countries.

A resolution adopted unanimously by the Security Council on June 8, 2004, noted that the multinational force would remain in Iraq at the request of the interim government about to assume control of the country from America and Britain.

The offensives are aimed at uprooting insurgents who have killed more than 620 people since a new Iraqi government was announced April 28.

Just before dawn, American Marines, sailors, and soldiers encircled this city 140 miles northwest of Baghdad in troubled Anbar province.

Helicopters swept down near palm tree groves to drop off Marines who blocked off one side of Haditha, while other troops on foot and in armored vehicles established checkpoints and moved toward the city center. American warplanes circled overhead.

American troops walked down city streets in neat lines, whispering instructions to each other. Except for dogs baying in the pre-dawn darkness, the city was quiet – until a large explosion shook the neighborhood.

Marines crouched with guns pointed, while others ran for cover, their ears still ringing from the explosion. One group ran through a front yard, rushing by a porch swing and a grove of trees. Sounds of battle and gunfire broke out around the city.

The Marines said six insurgents were killed in central Haditha – including one man identified as a cleric who allegedly was firing an automatic weapon. Four others were killed in separate incidents, the Marines said in a statement.

“Local citizens identified one of the attackers killed as an imam. The imam was firing on Marines and Iraqi Security Forces with an AK-47 assault rifle,” the statement said.

The first glimmer of dawn saw troops walking unimpeded, until a white sedan with four men appeared. The Marines quickly surrounded it, and the men got out, including one with a blood-soaked shirt who said he was shot after walking out of his home.

A small Iraqi reconnaissance unit took part in the attack, the commander of the 3rd Battalion, 25th Marine Regiment, Lieutenant Colonel Lionel Urquhart, said.

Iraq’s inability to fight the insurgency on its own was reflected in a letter to the United Nations from Zebari.

“Despite continuing efforts to build up our security forces, these forces cannot as yet assume full responsibility for maintaining our national security and defending our borders,” he wrote in the letter circulated yesterday.