BAGHDAD, Iraq -- About 600 U.S. Marines and Iraqi soldiers have launched a fourth counterinsurgency operation in less than a month in a volatile western province in Iraq, this time near Fallujah, the military said Saturday.
Operation Scimitar started Thursday with targeted raids in the village of Zaidan, 20 miles southeast of Fallujah. So far, 22 suspected insurgents had been detained. Fallujah, 40 miles west of Baghdad, was a major insurgent bastion until U.S. forces overran the city in November.
The military said it did not announce the offensive earlier because commanders did not want to tip off insurgents that a major operation had begun. The campaign -- named after a curved Asian sword -- includes 500 Marines from the 3rd Reconnaissance Battalion, Regimental Combat Team-8, stationed in Okinawa, Japan, the military said.
About 100 Iraqi soldiers were supporting the operation, which is designed to disrupt insurgent activity in the Anbar province.
The latest counterinsurgency offensive in the province came on the heels of Operations Spear, Dagger and Sword. There are a number of insurgent strongholds in Anbar, which stretches from Baghdad to the Syrian border.
The heaviest fighting occurred during Operation Spear in mid-June in the town of Karabilah near the porous Syrian border, which intelligence officials believe is the main gateway for foreign fighters entering Iraq.
The military said it killed about 50 insurgents in airstrikes, tank shelling and gunbattles during Operation Spear. Sections of Karabilah were left in rubble.
The insurgency has frequently targeted Iraq's security forces, but started focusing on attacking foreign diplomats in recent days as part of a new trend apparently aimed at isolating the country from the Arab world.
A roadside bomb hit an American convoy in the central city of Samarra, damaging one Humvee, police Capt. Laith Mohammed said. There no immediate reports of casualties. A separate mortar attack in downtown Samarra wounded three women, he said.
At the G-8 summit in Scotland, Italian Premier Silvio Berlusconi said his government would begin withdrawing about 300 troops from Iraq in September -- subject to security conditions at the time.
The moves came as violent incidents in the Iraqi capital are declining since Iraq's U.S.-backed forces launched an operation against insurgents in the city six weeks ago.
The commander of U.S. forces in Baghdad, Maj. Gen. William G. Webster Jr., said car bombings had dropped from 14 to 21 a week in May to about seven or eight a week now. But he said it was "very difficult to know" whether the insurgency has been broken.
Iraqi officials have become concerned about a possible exodus of diplomats from Baghdad after a Web site claim Thursday by al-Qaida in Iraq that it had killed Egyptian envoy Ihab al-Sherif, who was seized by up to eight gunmen on a street in western Baghdad last weekend.
Egyptian and Iraqi officials said Egypt would temporarily close its mission in Iraq and recall its staff -- although al-Sherif's body has not been found and the Web statement contained no photographic evidence of his death.
Pakistan's Ambassador Mohammed Younis Khan left the country Wednesday after his convoy was fired on in a kidnap attempt. Bahrain's top envoy, Hassan Malallah al-Ansari, was expected to leave soon after he was slightly wounded in a separate attempt.
In its Web statement, the country's most feared terror group said it wanted to seize "as many ambassadors as we can" to punish governments that support Iraq's Shiite-dominated government.
Sunni Arabs, who dominated Iraq until fellow Sunni Saddam Hussein was ousted in 2003, boycotted January elections and now make up the core of an insurgency that has killed more than 1,475 people since the Shiite- and Kurdish-led government took office on April 28.