After the Shiite al-Mahdi Army led by cleric Muqtada al-Sadr retreated from police stations and governmental buildings in Najaf, Karbala and Kufa as demanded by the United States, a US commander in Iraq said Monday they would "kill or capture" al-Sadr.

The cease-fire is seeking to restore stability after fighting erupted on April 1 across Iraq. The violence has killed about 900 Iraqi people and 70 US-led coalition troops. It was the biggest loss of life since the ousting of former President Saddam Hussein.

"Al-Sadr issued instructions for his followers to leave the sites" of police stations and governmental buildings of three cities, said al-Sadr's spokesman on Monday. The US military has send more troops to Falluja and Najaf where al-Sadr's office is located, saying they would re-occupy the cities if talks fail.

Top US commander in Iraq Ricardo Sanchez said "the mission of US forces is to kill or capture Muqtada al-Sadr."

Four US soldiers were killed and another four injured near Baghdad on Monday, said the US military. Several US tanks and armored vehicles on Monday surrounded a university in Baghdad, warning armed students to surrender.

In Karbala the United States sent leaflets by aircraft, asking people to stay away from the military bases of the coalition forces and voicing revenging intentions if being attacked.

Several Iraqi gunmen attacked a convoy of flatbed trucks carrying M113 armored personnel carriers and set them on fire in the south of Baghdad.

In Washington, head of the US Central Command John Abizaid saidMonday that he has asked for two more combat brigades for Iraq.

Speaking to reporters at a teleconference between Baghdad and Washington, Abizaid said he had asked for "a strong mobile combat arms capability."

He said he had requested for two bridges worth of combat power,and he was working on the details with the US Joint Staff.

Meanwhile, two US soldiers and seven US contractors working fora Halliburton subsidiary were unaccounted for in Iraq, Ricardo Sanchez, who is in charge of US military operations in Iraq, said at the press conference.

Abizaid said some of the response of Iraqi forces to insurgentsin the country had been "a great disappointment."

"In the south, a number of units, both in the police force and also in the ICDC (Iraqi Civil Defense Corps) did not stand up to the intimidators of the forces of (Moqtada) Sadr's militia and that was a great disappointment to us," he said.

Around Fallujah, the forces had shown "good, strong performances by several units and we're satisfied with that," he said

He acknowledged difficulties in equipping and training, and said some changes would be made.

Eleven Russian employees of the Russian International Company for Energy Services have been kidnapped in Baghdad, the Qatar-based al-Jazerra television said on Monday.

Seven Chinese abducted in Iraq were released late Monday night and they are safe now in a temporary residence in Baghdad.

The seven's health and spiritual conditions are generally stable, a Chinese Foreign Ministry spokesman said Tuesday morning in Beijing.

After they arrived in the residence, Sun Bigan, head of the team responsible for the re-establishment of the Chinese Embassy in Baghdad, immediately conveyed cares from Chinese President Hu Jintao and other Chinese leaders to all of the men, the spokesman said.

On Sunday the Czech embassy in Baghdad said two Czech television employees disappeared north of the capital.

Source: Xinhua