U.S. forces were back patrolling the streets of the predominantly Shiite city of Balad on Tuesday after five days of sectarian slaughter killed 95 people, violence that surged out of control despite the efforts of Iraq's best-trained soldiers.

Iraq's 4th Army took command of the region north of Baghdad a month ago, but had been unable to stem recent attacks in Balad, where the slayings of 17 Shiite Muslim workers on Friday set off revenge killings by Shiites.

Minority Sunnis, who absorbed most of the brutality in the city of 80,000 people, have been fleeing across the Tigris River in small boats, Balad police commander Brig. Nebil al-Beldawi said. On the outskirts of the city, two fuel trucks were attacked and burned.

Visit FOXNews.com's Iraq Center for more in-depth coverage.

The police commander said gunmen wearing black uniforms, trademark clothing of Shiite militiamen, had clashed with residents of Duluiyah, a predominantly Sunni city on the east bank of the Tigris, opposite Balad. Al-Beldawi said the militants were keeping food and fuel trucks from entering Duluiyah.

The conflict between Shiites and Sunnis in the Balad area illustrates the threat to the region should Iraq move toward dividing into three federal states — controlled by Shiites in the south, Sunnis in the center and Kurds in the north.

CountryWatch: Iraq

Regions such as Baghdad and areas immediately to the north, including Balad, are now home to Shiites and Sunnis. Both groups would be expected to fight hard to maintain control of their territory, especially in the capital.

Last week, over the objection of nearly all Sunnis and some Shiites, the Shiite-dominated parliament voted to allow moves toward establishing federal states after an 18-month waiting period.

Dividing the country would close Sunnis off from oil wealth, which would end up with the Kurds in the north and the Shiites in the south. Sunni lands are largely desert or agricultural belts along the Tigris and Euphrates rivers.

Forty mortar rounds poured into Balad overnight and into the morning, killing at least four people, bringing the death toll in the area to at least 95 in five days of fighting.

Gunmen in police uniforms hijacked 13 civilian cars and abducted their occupants at a checkpoint outside Balad on Monday night, Salahuddin provincial police reported. They remained missing Tuesday.

Elsewhere in Iraq, 36 people were killed Tuesday in violent attacks and 16 more corpses were found in the capital, their hands and legs bound and showing signs of torture, police reported.

According to an Associated Press count, October is on track to be the deadliest month for Iraqis since the AP began tracking deaths in April 2005. In October, 767 Iraqis have been killed in war-related violence, an average of 45 every day.

That compares to an average daily death toll of about 27 since April 2005. The AP count includes civilians, government officials and police and security forces, and is considered a minimum based on AP reporting. The actual number is likely higher, as many killings go unreported.

Iraqi officials, particularly Prime Minister Nouri al-Maliki, are under intense pressure to disband Shiite militias believed responsible for most of the killings in Balad and heavy involvement in violence elsewhere.

The fighters, allied to Shiite political groups, are widely believed to have infiltrated the Shiite-dominated police and security forces and to be allowed freedom to attack Sunni Muslims without fear of arrest or interference.

In apparent response to that pressure, the Interior Ministry, which runs the Iraqi police, removed two officers in charge of commando units as part of a restructuring plan announced last week.

Brig. Abdul-Karim Khalaf, the ministry's spokesman, said Maj. Gen. Rashid Filah and Maj. Gen. Mahdi Sabbih were transferred from their posts, but denied their removal was a demotion or had anything to do with militia activity.

"Because of their sacrifices and their experience, both of these leaders were named to high-ranking posts," Khalaf said, flanked by Filah and Sabbih.

The ministry said last week it had fired 3,000 employees accused of corruption or rights abuses and that it intended to change top commanders as part of a restructuring plan designed to bolster its ability to combat violence. It said 600 of the 3,000 dismissed personnel will face prosecution.

The U.S. military symbolically handed control of parts of Salahuddin province to the 3rd Battalion, 1st Brigade, 4th Iraqi Army Division on April 15. That region included Balad and Duluiyah, as well as surrounding villages. Full control of the province was officially turned over to the 4th Army on Sept. 18.

Under such shifts of control, U.S. forces do not necessarily withdraw, but are deployed to local bases to stand by as backup. Since the latest security crackdown in Baghdad, however, U.S. forces from many regions have shifted to the capital, causing a drawdown of American troop strength in some regions of the country.

On Sept. 7, the U.S. military handed over control of Iraq's armed forces command to al-Maliki's government. Previously, the U.S.-led Multinational Forces in Iraq, commanded by Gen. George Casey, gave orders to the Iraqi armed forces through a joint American-Iraqi headquarters and chain of command. Senior U.S. and coalition officers controlled larger units, which were in turn commanded by Iraqi officers.

Now, the chain of command flows directly from al-Maliki in his role as Iraqi commander in chief, through the Defense Ministry to an Iraqi military headquarters. From there, the orders flow to Iraqi units on the ground.

As the violence in the Balad region was reaching full pitch on Saturday, the AP asked the U.S. military in Baghdad if American forces were involved in trying to quell the killing.

"As of this time, the (U.S.-led force in Iraq) has not been asked to provide any assistance," the military said in a return e-mail. A request for information on Sunday went unanswered.

In response to the same question on Monday, the military responded that U.S.-led forces were "partnering with Iraqi police and Iraqi army units involved in operations around Balad."

On Tuesday morning, the military said the U.S.-led force was again "partnering with and assisting the Iraqi police and army by providing quick reaction assets. The Iraqi police and army are currently manning numerous checkpoints around Balad."

By late Tuesday, the military had not responded to questions about when the U.S. military first was asked to intervene and how many American forces were involved.

Complete coverage is available in FOXNews.com's Iraq Center.