Radical Shiite cleric Muqtada al-Sadr threatened Friday to unleash suicide bombers if U.S. troops move against him in Iraq’s holiest Shiite city, and his militiamen attacked a Bulgarian convoy, killing a soldier. Meanwhile, police in Basra arrested five Iraqis believed linked to al-Qaida and suspected in brutal suicide bombings Wednesday that killed 74 people. The five men were captured with a total of nearly 25 tons of TNT, and police were looking for another car bomb they suspected was somewhere in the mainly Shiite city in the far south of Iraq, said Basra’s police intelligence chief Khalaf al-Badran. Full Story