Almotamar.net - Rare evidence of simmering tensions between Shiite factions boiled into public view Wednesday when followers of radical cleric Muqtada Sadr stormed the office of a rival Shiite political party in southern Iraq, wounding nine people and prompting a city-wide daytime curfew, according to police and hospital officials.

The assault seems to have been prompted by a dispute between Sadr followers and a member of the Fadhila political party within the Electricity Ministry that serves the area. The governor's house was also attacked.

It came just one day after three alleged Sadr followers in the southern city of Kut stopped the mayor's car at a fake road block and shot him to death, with the help of six members of the local police force.

There is a struggle for control of the government in the area, which is run by affiliates of the largest Shiite bloc in parliament, although it is being challenged by supporters of Sadr.

The three Sadr followers involved in the assassination were killed and the six police officers have been arrested, according to local police. Kut was also under a full curfew today.

Meanwhile, the U.S. military announced it had captured several members of a group responsible for a brazen January attack on a troop station in Kerbala in which four soldiers were kidnapped and later killed, including a top aide to Sadr.

At the same time, the military said that at the request of Iraqi Prime Minister Nouri Maliki, it was releasing a Sadr aide it has held for more than two years. U.S. forces also found and destroyed a car bomb factory in Baghdad and arrested an Al Qaeda operative who was running it.

Also today, an explosion rocked the building where U.N. Secretary-General Ban Ki-moon was appearing with Maliki at a news conference broadcast on live television.

Ban, who was visiting for Iraq for the first time after becoming secretary general, had just finished answering a question about whether or when the U.N. might re-establish full-fledged operations here when a rocket or mortar round struck nearby.

No one was injured, but Ban was shaken. He ducked, looking shocked. Maliki and Ban took one more question before the session ended. The Associated Press reported that the rocket landed about 50 yards away.

The U.N. curtailed its presence in Iraq after its Baghdad headquarters were leveled in a car bomb attack in 2003, which killed 22 people including Sergio Vieira de Mello, the U.N.'s top envoy here. It now conducts most of its Iraq operations from Jordan.

Moon had said he would consider re-opening a U.N. office here as "the situation on the ground" improves.

Meanwhile, gunmen engaged in firefights with Iraqi army soldiers on the streets of Baghdad today, and a roadside bomb and a car bomb killed one and injured three in the Amiriya neighborhood.

Gunmen also opened fire on a mini-bus as it passed through the Sunni insurgent stronghold of Dora, killing one passenger and injuring two others.

christian.berthelsen@latimes.com