Special report: Tension escalates in Iraq

    BAGHDAD, April 6 (Xinhua) -- U.S. and Iraqi forces launched on Friday an extensive military operation dubbed "Operation Black Eagle" in the troubled province of Diwaniyah, some 180 km south of the capital, the U.S. military said.

    "Soldiers of the 8th Iraqi Army Division supported by soldiers and paratroopers from Multi-national Division-Baghdad began Operation Black Eagle at approximately 6:30 a.m.(0230 GMT), in response to the recent violence threatening to destabilize the region (Diwaniyah)," the military said in a statement.

    A local police source told Xinhua that clashes erupted in the city during the day between U.S. troops and Mahdi Army, a militia loyal to radical Shiite cleric Muqtada al-Sadr.

    The clashes took place when the U.S. troops blocked the neighborhoods of Jumhouriya, Nahda, Oruba and Iskan in preparation for search operations, said the source who requested anonymity.

    For its part, the Sadr Office in Diwaniyah issued a statement saying a US tank and two Hummers were set ablaze during the clashes, adding that three members of the Mahdi militias were wounded.

    Muqtada al-Sadr has called for massive demonstrations in Iraqi cities on Monday, the fourth anniversary of Baghdad's occupation by U.S. forces.