Dozens of insurgents were killed by coalition forces on Saturday, said CNN, which had a reporter embedded with the U.S. forces. A New York Times reporter on the scene said at least two American service members were wounded.
Two Sunni Arab politicians sharply criticized the Husaybag offensive.
Brig. Gen. Donald Alston told reporters Sunday that no U.S. or Iraqi forces had been killed. He had no information about possible insurgent casualties in the mostly Sunni-Arab area.
"We are having contact with the enemy, but we are not meeting stiff resistance," Alston said. "They are using small arms fire."
But CNN reported that during one 20-minute firefight in the city center on Saturday insurgents fired at U.S. Marines and Iraqi forces from inside a mosque. In a southwestern part of Husaybah, machine gun fire, tank rounds and AK-47 bullets reverberated during tough street-by-street combat, the network said.
The New York Times reported Sunday that coalition forces supported by tanks and fighter jets dropping 500-pound bombs met more resistance than expected from insurgents in the town of Husaybah, and only managed to take control of several blocks by nightfall Saturday.
At least two U.S. service members were wounded by sporadic enemy fire down alleyways as U.S.-led forces advanced in the town house by house, searching each one, the Times reported.
"We met more resistance than I expected," U.S. Capt. Conlon Carabine of Indian Company of the Third Battalion, Sixth Marine Regiment, told the Sunday Times.
The coalition forces sometimes found it hard to spot insurgents hiding in the town's 4,000 homes and called in support from Abrams tanks and fighter jets, the Times said.
But the soldiers also discovered that many families had fled Husaybah during the past several weeks, having been tipped off about the offensive ahead of time or having assumed that one was likely in the insurgent stronghold, the Times reported.
In Baghdad, Mohsen Abdul-Hamid, head of the Iraqi Islamic Party, a moderate Sunni Arab bloc, issued a statement sharply criticizing the offensive.
"We reject all military operations directed against civilian targets because such acts lead to the killing of innocent people and the destruction of towns and cities," he said.
The offensive also was criticized by Saleh al-Mutlaq, head of another Sunni faction, the National Dialogue Council. "American forces accompanied by what is called the Iraqi army and national guard are conducting a destructive and killing operation of secure cities and villages on the pretext that they hide and secure terrorists."
The "Operation Steel Curtain" offensive in Husaybah is aimed at sealing off a main route for foreign fighters entering Iraq and was seen as a key to controlling the volatile Euphrates River valley of western Iraq and dislodging the insurgent group al Qaeda in Iraq.
The U.S.-led operation, which included about 1,000 Iraqi soldiers, also will serve as a major test of their capability to battle the insurgents, seen as essential to enabling Washington to draw down its 157,000-strong military presence.
"The insurgents are throwing everything they have at the Iraqi people and coalition forces in an effort to derail Iraq's democratic reforms," Alston said.
He said the offensive is aimed at interrupting the supply lines that al Qaeda in Iraq uses to launch some of the deadliest suicide attacks Iraq suffers in crowded cities such as Baghdad.
When the offensive began early Saturday, thunderous explosions shook Husaybah as U.S. Marines and Iraqi scouts, recruited from pro-government tribes from the area, fought their way into the western neighborhoods of the town, residents said.
As the fighting continued in "Operation Steel Curtain," 200 miles northwest of Baghdad, coalition forces encountered sporadic resistance, mostly small arms fire and IEDs, "improvised explosive devices" or roadside bombs, the U.S. command statement said.
One of nine coalition air strikes destroyed a suspected suicide car bomb, and six other bombs and land mines were discovered by U.S. and Iraqi ground forces, the military said.
Iraqi soldiers also established temporary lodging in a vacant area of Husaybah to provide shelter and food for about 400 local residents, the military said.
The U.S. military said three of its soldiers were killed in other areas of Iraq. One soldier was killed Friday by small-arms fire south of Baghdad, and another died the same day when the vehicle in his patrol was hit by a mine near Habaniyah, 50 miles west of the capital. The third soldier was killed Saturday in a traffic accident in southern Iraq.
Those deaths raised to at least 2,045 the number U.S. service members who have died since the beginning of the Iraq war in March 2003, according to an Associated Press count.
U.S. commanders hope the Husaybah offensive will restore control of western Anbar province ahead of Iraq's parliamentary election Dec. 15 and enable Sunni Arabs there to vote. Sunnis form the vast majority of the insurgents, and U.S. officials hope that a strong Sunni turnout next month will encourage many of them to lay down arms and join the political process.
Husaybah, a poor Sunni Arab town of about 30,000 people, is the first stop in a network of communities that the U.S. military suspects al Qaeda of using to smuggle fighters, weapons and explosives from Syria down the Euphrates valley to Baghdad and other cities.
Many Husaybah residents are believed to have fled the town after weeks of fighting between Iraqi tribes that support the insurgents and those that back the government.
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