BAGHDAD - Iraqi soldiers fired in the air over supporters of anti-American Shi'ite cleric Moqtada al-Sadr to prevent them from gathering for Muslim prayers yesterday in the southern city of Basra, enraging the worshipers and straining a fragile truce with the government.
In another worrisome sign, a top aide to Sadr accused Iraqi forces of violations of a separate truce in Baghdad's Sadr City, where thousands of Iraqi troops have deployed in what has been a peaceful campaign to impose control.
Sadr Movement officials in both Basra and Sadr City said they were abiding by the cease-fires, but the shooting in the southern city angered Sadr's followers throughout southern Iraq and in Baghdad.
The cease-fires are crucial to Iraqi security forces' sweeps in Basra and Sadr City, launched by Prime Minister Nouri al-Maliki to show that his government can spread its authority in areas long dominated by armed groups like Sadr's powerful Mahdi Army militia.
In a separate development yesterday, the US military said more than 180 suspected Sunni Arab insurgents turned themselves in to Iraqi authorities in the city of Balad, 50 miles north of Baghdad. It called the surrenders a sign of progress in efforts to persuade insurgents to end their fight against American forces.
The surrenders came after a series of raids that resulted in the deaths of three individuals. The area has seen significant fighting between US-Iraqi forces and Al Qaeda in Iraq.
Iraqi police in Basra said one person was wounded in the shooting in a square in the northern part of the city. But Sadr officials contended that one person was killed and three wounded.
The confrontation began when about 75 Sadr supporters tried to gather in Basra's Mile-5 Square to hold Friday prayers, witnesses said. Iraqi police recently banned Sadr gatherings in the square after a large cache of weapons was found nearby, police officials said, speaking on condition of anonymity because they feared retaliation.
Iraqi troops were deployed at the square to prevent the prayers. When those gathering refused to disperse, the police fired rounds over their heads, witnesses and the police officials said.
"Oh al-Sadr, to whom we should complain, al-Maliki is just like Saddam Hussein," the worshipers chanted, according to the witnesses.
In the Shi'ite holy city of Kufa, 210 miles northwest of Basra, a senior aide to Sadr, Abdul-Hadi al-Mohammadawi, denounced the altercation. In a sermon, he said the security forces "opened fire on worshipers" and that one person was killed.
Still, an official in Sadr's office in Basra said the group would maintain the truce.
When Iraqi forces began their sweep in Basra in late March, it sparked heavy fighting with the Mahdi Army, which also launched a wave of violence across southern Iraq and in Sadr City. The fighting in Basra and the rest of the south ended with a truce, mediated by Iran, in mid-April.
Since then, Iraqi security forces have continued raids to arrest wanted figures among the many Shi'ite militias in Basra, and the troops appear to have greater control of the streets in many districts.
Violence has been reduced considerably.