Updated

Gunmen assaulted two Sunni mosques and sprayed bullets into Sunni homes in a mixed neighborhood Tuesday in sectarian violence that killed three people and wounded 15, many of them attackers suspected of being followers of a radical Shiite cleric.

The latest deaths brought the number of people killed by attacks in and around Baghdad Tuesday to 24, police said.

Police in Baghdad also found the bodies of 23 men apparently slain by the sectarian death squads terrorizing the Iraqi capital.

Underscoring Iraq's divisions, more cracks appeared in a Sunni Arab agreement to support legislation that Shiites hope will lead to a self-ruled Shiite state in southern Iraq. Many Sunnis fear that would splinter Iraq and deny their minority a share of its oil wealth.

The attacks on Sunni targets began when the al-Ashra al-Mushara mosque in al-Amel district was stormed about 4:30 p.m. by gunmen in black uniforms, which are often associated with the Mahdi Army militia loyal to anti-U.S. Shiite cleric Muqtada al-Sadr. Two passers-by were wounded.

CountryWatch: Iraq

About 15 minutes later, black-clad gunmen attacked Sunni homes in the same western neighborhood. Residents fought back, wounding five of the militants, while three civilians and a police officer were also injured, police Lt. Maithem Abdul Razzaq said.

The wounded attackers were captured and identified as Mahdi Army members, Razzaq said.

Three gunmen died in an attack on the Sunnis' al-Kheyr mosque in Khadra, another western neighborhood, police said. No other details were released.

On the eastern side of the city, meanwhile, the bodies of 23 men were found dumped in streets, all with bullet wounds and most showing signs of torture — hallmarks of sectarian killings that have raged since a Shiite shrine was bombed in Samarra last February.

The bloodshed came as U.S. and Iraqi troops finished two weeks of building-by-building sweeps in Shaab and Ur, north Baghdad neighborhoods that have been strong supporters of al-Sadr.

The campaign to clear the capital district by district was launched this summer after U.S. generals warned that escalating sectarian violence was threatening to bring civil war. Sweeps have been started or completed in about half the city's neighborhoods.

Col. Michael Shields, whose 172nd Stryker Brigade Combat Team provided much of the muscle for the operation, said the operation in Shaab and Ur now goes into the "protect and securing" phase where the focus will be on projects to improve the area's infrastructure.

Sectarian divisions continued to roil parliament.

A Sunni Arab heading a parliamentary committee that reviews new legislation resigned to protest the Shiite-sponsored federalism bill, warning it would lead to further instability and bloodshed.

The move by Dahfir al-Ani deepened a crisis in the Sunni Arab community and his Iraqi Accordance Front, the minority's largest political coalition and the group that brokered a compromise with Shiite and Kurdish groups to allow introduction of the federalism bill.

"Putting this issue under discussion at this time would open the door for political crisis that would more threaten the security situation," al-Ani said. "As for me, I will try along with my brothers who share with me the same opinion to foil the voting in favor of this bill."

Another member of the Accordance Front accused the political bloc of betraying the Sunni Arab community. "This law will lead to the division of Iraq, and the Accordance Front has carried out an act of treason," Abdul Nasser al-Janabi told parliament.

Iraq's second-largest Sunni group, the National Dialogue Front, already rejected the deal and says it will fight any effort to set up more self-rule regions like the autonomous Kurd area in the north.

The Accordance Front agreed to allow debate on the bill in return for Monday's formation of a parliamentary committee to study amending the constitution adopted last fall.

Sunnis hope to amend the charter to make it difficult to create self-rule zones, but any change would have to be approved in a national referendum and Shiite Arabs and Kurds make up about 80 percent of the population.

The Shiite-sponsored federalism bill was read in parliament Tuesday and will be debated in committee for two days. It could be voted into law as early as Oct. 5, although the compromise will delay its implementation until 2008 to allow time for the amendment process.

Sunni Arabs fear that setting up more self-rule regions could break up the country and leave them without a share of Iraq's oil, which is found in the predominantly Kurdish north and the heavily Shiite south.

In other violence, explosions killed at least 21 people and wounded dozens in and around the capital, police said.

In the deadliest incident, at least seven civilians died and 11 were injured when a series of explosions rocked a predominantly Shiite apartment building in Mahmoudiya, about 20 miles south of Baghdad, police said. The explosions gutted a series of apartments.