BAGHDAD (AP) – Iraqi and U.S. troops fanned out in a devastated Sunni neighborhood in Baghdad on Friday, residents said, adding they were holed up in their houses under a curfew that was imposed to restore calm after days of internal fighting between insurgent groups.

Northeast of Baghdad, an al-Qaeda-linked suicide bomber blew himself up Friday in a house sheltering members of the rival 1920 Revolution Brigades, killing two of the other militants and wounding four in the strife-ridden city of Baqouba, police said.

The developments were the latest in an apparently growing Sunni insurgent power struggle as U.S. and Iraqi officials try to isolate the terror network by turning other militant groups and tribal leaders against it. The tactic has proven relatively successful in the western Anbar province, once considered the heartland of the Sunni insurgency, and Washington and the Iraqi government are trying to replicate it elsewhere.

Lt. Gen. Raymond Odierno, the No. 2 U.S. commander in Iraq, said Thursday that U.S. military officers were talking with Iraqi militants, excluding al-Qaeda, about cease-fires and other arrangements to try to stop the violence. He said he thinks 80 percent of Iraqis, including Sunni insurgents and Shiite militants, can reach reconciliation with each other, although most al-Qaeda operatives will not.

The leader of Iraq’s largest Shiite party, meanwhile, returned to Baghdad from Iran after completing the first phase of his treatment for lung cancer, according to the Web site of the Supreme Islamic Council of Iraq.

Abdul-Aziz al-Hakim thanked Iraq’s top Shiite cleric Ayatollah Ali al-Sistani and the Iraqi government for their support.

“I promise almighty God and the Iraqi people to be loyal to the principles that I pledged to defend the dignity of Iraqi people and achieve their aspirations and wishes for freedom and independence,” he was quoted as saying.

Abu Ahmed, a 40-year-old Sunni father of four in Baghdad’s Amariyah neighborhood, said he was among a group of residents who joined in the clashes with al-Qaeda fighters on Wednesday and Thursday, fed up with the gunfire that kept students from final exams and forced people in the neighborhood to huddle indoors.

Ahmed denied being a member of any insurgent groups but said he sympathizes with “honest Iraqi resistance,” referring to those opposed to U.S.-led efforts in Iraq but also against the brutal tactics of al-Qaeda.

“Al-Qaeda fighters and leaders have completely destroyed Amariyah. No one can venture out and all the businesses are closed,” he said. “They kill everyone who criticizes them and is against their acts even if they are Sunnis.” “What al-Qaeda fighters do is not jihad (holy war), these acts are just criminal ones. Jihad must be against the occupation, Shiite militias and those who cooperate with them,” he added. “Those fighters are here only to kill Iraqis and not the Americans.They are like cancer and must be removed from the Iraqi body.”

Other residents, who spoke on condition of anonymity because they feared retribution, said the clashes began after al-Qaeda abducted and tortured Sunnis from the area, prompting a large number of residents, many members of the rival Islamic Army armed with guns and rocket-propelled grenades, to rise up against the terror network.

Official casualty figures were not immediately available.

But a local council member, who declined to be identified because of security concerns, said at least 31 people, including six al-Qaeda militants, were killed and 45 other fighters were detained in the clashes.

Lt. Col. Dale C. Kuehl, commander of 1st Battalion, 5th Cavalry Regiment, who is responsible for the Amariyah area of the capital, confirmed the U.S. military’s role in the fighting in the Sunni district. He said the battles raged Wednesday and Thursday but died off at night.

Although al-Qaeda is a Sunni organization opposed to the Shiite Muslim-dominated government, its ruthlessness and reliance on foreign fighters have alienated many Sunnis in Iraq.

The U.S. military and the Iraqi government congratulated Amariyah residents for standing up to al-Qaeda. “Government security forces are now in control of the Amariyah district,” Iraqi military spokesman Qassim al-Moussawi was quoted as saying by Iraqi state TV. He also lauded “the cooperation of local residents with the government.”

Saif M. Fakhry, an Associated Press Television News cameraman, was shot twice and killed in the turmoil in Amariyah on Thursday. Fakhry, 26, was the fifth AP employee to die violently in the Iraq war and the third killed since December. He was spending the day with his wife, Samah Abbas, who is expecting their first child in June. According to his family, Fakhry was walking to a mosque near his Amariyah home when he was killed. It was not clear who fired the shots.

The explosion in Baqouba, 60 kilometers (35 miles) northeast of Baghdad, came as residents said al-Qaeda is trying to regain control of the central Tahrir neighborhood from the 1920 Revolution Brigades, a group composed of officials and soldiers from the ousted regime who have allied themselves with local security forces against the terror network.

Mustafa Hadi, a 30-year-old man who lives in the neighborhood, said the insurgent group had set up several checkpoints and commandeered houses that have been vacated by Shiites and others fleeing the violence. “These soldiers use empty houses as resting places,” he said. “At night they ask the residents to light a bulb outside their homes to make it easy for them to watch the area.”