Soldiers from the Second Stryker Cavalry Regiment hold their weapons as the top U.S. Commander in Iraq, General David Petraeus, joins them for a patrol in Muqdadiyah, in the Diyala province July 26, 2008. Sunni Islamist al Qaeda has sought to stoke tensions in Iraq's ethnically and religiously mixed northern cities, such as Diyala and Mosul, after military campaigns pushed its militants out of former strongholds in western Anbar province and Baghdad. REUTERS/Damir Sagolj (IRAQ)