 Al-Sadr created the Mahdi Army in June 2003.The second cause, probably the flashpoint for the conflict, was the highly publicized killing and mutilation of four Blackwater private military contractors on March 31, 2004.Five days before American troops withdrew from Fallujah after intense fighting on March 26, 2004 (at which point Fallujah had already been declared insurgent-occupied) killed one Marine.