U.S. and Iraqi troops launched an operation designed to disrupt guerrilla activity in Ramadi on Friday ahead of Iraq's Dec. 15 elections, one day after insurgents staged a show of force in the western city. Some 300 American Marines and 200 Iraqi army soldiers began Operation Shank, the latest in a series of operations aimed at disrupting guerrilla networks in Anbar province, the heartland of the Sunni Arab-led insurgency. "The purpose of the operation is to disrupt a terrorist group that utilizes an area of Ramadi as its base for attacks on local Ramadi citizens, Iraqi and U.S. military," said a U.S. military statement, according to Reuters.