Shi'ite volunteers in support of the Iraqi Army visit the Imam al-Askari shrine in Samarra
Shi'ite volunteers in support of the Iraqi Army visit the Imam al-Askari shrine in Samarra July 12, 2014. Picture taken July 12, 2014. REUTERS/Thaier Al-Sudani (IRAQPOLITICS UNREST - Tags: CIVIL UNREST POLITICS RELIGION MILITARY)
Shi'ite volunteers in support of the Iraqi Army visit the Imam al-Askari shrine in Samarra
Shi'ite volunteers in support of the Iraqi Army visit the Imam al-Askari shrine in Samarra July 12, 2014. Picture taken July 12, 2014. REUTERS/Thaier Al-Sudani (IRAQPOLITICS UNREST - Tags: CIVIL UNREST POLITICS RELIGION MILITARY)
Shi'ite volunteers eat free meals given to them by supporters, at Samarra in Salahuddin province
Shi'ite volunteers eat free meals given to them by supporters, at Samarra in Salahuddin province, July 12, 2014. Picture taken July 12, 2014. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST CONFLICT POLITICS FOOD)
An off-duty Shi'ite volunteer from brigades loyal to radical cleric Muqtada al-Sadr takes up position with his weapon on a vehicle while returning home, in Samarra
An off-duty Shi'ite volunteer from brigades loyal to radical cleric Muqtada al-Sadr takes up position with his weapon on a vehicle while returning home, in Samarra, July 13, 2014. Followers of al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades." The black-turbaned cleric was shown on television this week surrounded by aides in camouflage poring over maps of deployments around Samarra. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT)
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home, in Samarra
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home, in Samarra, July 13, 2014. Followers of al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades." The black-turbaned cleric was shown on television this week surrounded by aides in camouflage poring over maps of deployments around Samarra. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT)
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr take a ride to return home, in Samarra
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr take a ride to return home, in Samarra July 13, 2014. Followers of radical cleric Muqtada al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades". REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS)
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home, in Samarra
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home, in Samarra, July 13, 2014. Followers of al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades." The black-turbaned cleric was shown on television this week surrounded by aides in camouflage poring over maps of deployments around Samarra. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT)
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return to home, in Samarra
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return to home, in Samarra, July 13, 2014. Followers of al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades." The black-turbaned cleric was shown on television this week surrounded by aides in camouflage poring over maps of deployments around Samarra. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT)
A Shi'ite volunteer from brigades loyal to radical cleric Muqtada al-Sadr, keeps guard as he mans a machine gun in Samarra
A Shi'ite volunteer from brigades loyal to radical cleric Muqtada al-Sadr, keeps guard as he mans a machine gun in front of a picture of Iraqi Shi'ite radical leader Muqtada al-Sadr, in Samarra July 13, 2014. Followers of radical cleric Muqtada al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades." The black-turbaned cleric was shown on television this week surrounded by aides in camouflage poring over maps of deployments around Samarra. REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS CONFLICT)
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home in Samarra
Off-duty Shi'ite volunteers from brigades loyal to radical cleric Muqtada al-Sadr, ride a vehicle as they return home in Samarra July 13, 2014. Followers of radical cleric Muqtada al-Sadr, who fought U.S. troops under the banner of the Mehdi Army during the 2003-2011 occupation, have returned as Sadr's new "Peace Brigades". REUTERS/Thaier Al-Sudani (IRAQ - Tags: CIVIL UNREST POLITICS)