Iraqi police say government forces and Mahdi Army militiamen are clashing in Baghdad's Sadr City district. A police officer says the two sides are using small arms, rocket-propelled grenades and light mortars. The officer spoke on condition of anonymity as he was not authorized to release information to the media. He says eight civilians have been injured, including 3 children. The fighting erupted Tuesday morning when Iraqi troops tried to enter the district, a stronghold of anti-American cleric Muqtada al-Sadr. Al-Sadr faces a government ultimatum to either disband his Mahdi Army or give up politics.