Two top aides to radical Shiite cleric Muqtada al-Sadr were detained early Thursday by U.S. forces in the southern city of Najaf, a spokesman for al-Sadr said.

Salah al-Obeidi, a spokesman for al-Sadr who delivers Friday prayers on behalf of the cleric in the nearby city of Kufa, and Muayed al-Khazraji, a leading aide from Baghdad, were taken in a raid by U.S. and Iraqi forces at about 1 a.m. local time, said Muhammed Jamil, a spokesman in the city some 100 miles south of Baghdad.

CountryWatch: Iraq

The incident was not immediately confirmed by U.S. forces.

Jamil said the cleric called on the followers of his Mahdi Army not to retaliate.

"Muqtada al-Sadr called on Jaish al-Mahdi (the Mahdi Army) to exercise calm and self control and not to be dragged into the American scheme to drive them into a new confrontation."

In another incident, a joint American and Iraqi patrol clashed with Mahdi Army forces in Diwaniyah, 80 miles south of Baghdad, in a raid to arrest a Mahdi Army leader, police said.

Two Iraqi soldiers were wounded and four injured, said police Capt. Abbas al-Bayati. An Iraqi armored personnel vehicle and a U.S. Humvee were damaged, but there were no immediate reports of American casualties, al-Bayati said.

Al-Bayati said he was still trying to confirm whether there were any Mahdi Army dead or wounded.

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