U.S. forces launched a major security operation around Ramadi on Sunday, saying they hoped to restore order to a western Iraqi city which has been in rebel hands for much of the past year. Troops from the 1st Marine expeditionary force, backed up by Iraqi security forces, imposed an 8 p.m. to 6 a.m. curfew in and around the city, 110 km (70 miles) west of Baghdad, as part of what has been dubbed Operation River Blitz. The operation "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 U.S. 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," Marines Major General Richard Natonski said in the statement. He described the militants as "intent on preventing a peaceful transition of power between the interim Iraqi government and the Iraqi transitional government", which is being formed in the wake of the Jan. 30 elections.