Seven precision-guided missiles were fired at heavily armed insurgents who were stopping and searching civilian cars at gunpoint near Karabilah, close to the volatile town of Qaim, the Marines said in a statement.
The insurgents were armed with AK-47 assault rifles, medium machine guns and rocket-propelled grenade launchers and had "set up a barricade on a main road to the city and were threatening Iraqi civilians," the military said.
U.S. warplanes backed by helicopters launched air strikes that began at 11:40 a.m. and ended at 4 p.m. "once all the targets were destroyed," the military said. Approximately 40 insurgents were killed and there were no Marines casualties.
"The coalition aircraft and fighter jets and attack helicopters from the 2nd Marine Aircraft Wing attacked the insurgent compound and surrounding area targeting the armed men," the statement said. "There are no reports of civilian casualties or collateral damage."
In other recent developments:
A former commando wearing a uniform blew himself up during roll call at the heavily guarded headquarters of an elite Iraqi police unit Saturday, officials said, as attacks in and around Baghdad killed at least 23 people.
Interior Minister Bayan Jabr, meanwhile, said an ongoing Iraqi-led offensive to weed out militants in the capital was a success and expressed confidence that the Shiite-led government would bring security to the country within six months.
The attack at the two-story Baghdad headquarters of the Wolf Brigade followed weeks of accusations against the Shiite Muslim-dominated force by Sunni Arab leaders, who accuse it of kidnapping and killing Sunnis, including clerics.
Jabr said the attacker was a former Wolf Brigade member who was targeting the commando force's commander, Brig. Mohammed al-Quraishi.
"Today's attack does not constitute an infiltration of the police forces," Jabr said. "The only thing left of the bomber was his head and feet."
Three people were killed in the blast, Jabr said, adding that police were searching for two of the suspect's former colleagues. A witness, Maj. Falah al-Mahamdawi, said five people were killed and seven wounded. The discrepancy could not immediately be reconciled.
Gunmen also opened fire on a minibus in Diyara, 30 miles south of Baghdad in the so-called Triangle of Death, killing at least 11 Iraqi construction workers employed at government and U.S. bases, police said.