In Baghdad, Iraq's Oil Minister Ibrahim Bahr al-Uloum narrowly survived an assassination attempt when a roadside bomb exploded Monday, although two of his bodyguards died.
Meanwhile, the U.S. military refuted statements by al-Qaida that the Islamist militant group had captured and killed two U.S. Marines in western Iraq. A statement posted Sunday on the Internet purportedly from an al-Qaida group said the two Marines were "executed" after U.S. forces failed to release Sunni women prisoners as demanded by the group. The military dismissed the claims as propaganda and said there were no reports of any deaths.
Over the weekend, American military commanders launched a new offensive called Operation Iron Fist along the Syrian border in the western province of Anbar. U.S. officials hope to root out Iraqi insurgents and block foreign fighters from crossing the border to aid insurgents.
About 1,000 American troops moved into the region to shut down an insurgent base in the town of Sadah and to increase security in the area before the Oct. 15 referendum on a new Iraqi constitution.
Sunni leaders, meanwhile, continue to quarrel with Shiite and Kurdish politicians over the new constitution. The Iraqi parliament passed a Shiite-Kurdish proposal that will make it easier for the referendum to pass. The Sunni minority opposes the constitution but lacks the number of seats in parliament to defeat the change.
The new election rules dictate that for the referendum to pass, a majority of voters must agree to it, while for it to be defeated, two-thirds of registered voters in three or more provinces have to vote "no." In elections in January, less than 60 percent of Iraqis who registered actually voted, which sets a much higher benchmark for voters who oppose the referendum.
Opponents of the proposal say it sets a double standard, while supporters stress the importance of passing the referendum for Iraq's political stability.