US Marines and Iraqi troops set up checkpoints and imposed an 8 p.m. to 6 a.m. curfew on the rebellious city of Ramadi today, part of a nationwide effort to restore order after last month's election.
It was not clear if the troops of the 1st Marine expeditionary force and Iraqi soldiers, launching Operation River Blitz, would carry out a larger offensive on Ramadi, 110 km (70 miles) west of Baghdad, which has essentially been in guerrilla hands for most of the past year.
It is less than three months since a major Marines' offensive against the former rebel stronghold of Falluja, just east of Ramadi, which the US military took back from insurgents after three weeks of furious fighting.
"Operation River Blitz is designed to target insurgents and terrorists who have attempted to destabilize the Anbar province by terrorizing the populace through wanton acts of violence and intimidation," the US military said in a statement.
"We were asked by the Iraqi government to increase our security operations in the city to locate, isolate and defeat anti-Iraqi forces and terrorists," said Major General Richard Natonski, commander of the 1st Marines expeditionary force.
The operation follows a series of suicide bombings and other attacks on Shi'ite Muslims, killing at least 50, while they were marking Ashura, the most important day in the Shi'ite religious calendar.