The U.S. military has claimed on Monday that its Air Force has destroyed an al-Qaeda in Iraq training base south of Baghdad. The fighter jets have dropped eight big bombs in a large area in the district of Arab Jabour, used to manufacture bombs, stash weapons caches and train and launch sniper attacks at U.S. military convoys, the military said.Also on Monday, representatives of Shiite cleric Muqtada al-Sadr and parliament members from Iraq's main Shiite political bloc have signed a four-day cease-fire in an effort to end seven weeks of fighting in Baghdad's Sadr City slum.