Updated

Militants bombed the house of a prominent anti-Al Qaeda Sunni cleric, seriously wounding him and killing three of his relatives as the terror network apparently steps up its campaign against Sunnis who have turned against it.

The attack, which was followed by a fierce firefight, came after Sheik Wathiq al-Obeidi called on residents in the northern Baghdad neighborhood of Azamiyah to rise up against foreign fighters, a reference to Al Qaeda in Iraq, which recently has seen a surge in opposition from fellow Sunnis.

A Sunni insurgent umbrella group had threatened the cleric on Tuesday calling him a traitor and accusing him of working with the Anbar Salvation Council, an alliance of Sunni tribal leaders who are fighting Al Qaeda in Iraq in the province of the same name west of Baghdad.

"The so-called Wathiq and his followers ... are a legitimate target for mujahedeen (holy warriors)," the statement said.

Followers denied the cleric, a former preacher at the Abu Hanifa mosque, was linked to the U.S.-backed Anbar group.

But he issued his own call against Al Qaeda in Iraq last week during a funeral prayer for two nephews killed by militants believed to be linked to the group.

"We have to fight foreign fighters in our city," witnesses quoted him as saying. "We have to fight those linked to Al Qaeda in Azamiyah."

The explosion struck al-Obeidi's house before dawn and was followed by gunfire that resounded across the predominantly Sunni neighborhood.

The cleric, a former preacher at the Abu Hanifa mosque, was seriously wounded and his brother and two female relatives were killed, according to the head of the neighborhood council Dawood al-Azami.

Azamiyah is one of the most dangerous neighborhoods in Baghdad and has been surrounded by a security barrier as the U.S. and Iraqi militaries try to assert control over the area.

On the political front, the largest Sunni bloc in Iraq welcomed the international community's decision to expand the U.N. role in Iraq and open the door for the world body to promote talks to ease Iraq's sectarian bloodshed.

The broader U.N. initiatives on Iraq — which could begin next month — were supported by Washington in an apparent bid to bring together Iraqi factions and neighboring countries under an international umbrella rather than struggling on its own to bridge the many religious, ethnic and strategic battles opened by the five-year-old war.

The resolution adopted Friday by the Security Council authorizes the United Nations — at the request of the Iraqi government — to promote political talks among Iraqis and a regional dialogue on issues including border security, energy and refugees as well as help tackling the country's worsening humanitarian crisis which has spilled into neighboring countries.

The United States and Britain, co-sponsors of the resolution, believe the world body should do more to use its perceived neutrality to promote dialogue on Iraq.

"The U.N. is a neutral party that can play a good role in Iraq. They have played good role previously and now, we need them to re-activate that role and expand it, so we welcome this renewed chance for them here in Iraq," said Salim Abdullah, a spokesman for the Iraqi Accordance Front, the largest Sunni political bloc in parliament.

"Finding a third party, however, does not lift the responsibility from the shoulders of the American administration," he added. "It should be clear for the political powers inside Iraq that they cannot completely rely on the U.N., which should have a complementary role."

The U.S. command here has pointed repeatedly to the Anbar group and its opposition to Al Qaeda as an example for other tribes to follow elsewhere in Iraq and similar alliances have been formed among Sunnis in parts of the capital and in the volatile Diyala province to the north, putting the group on the defensive as it seeks to assert its dominance.

In other violence reported by police on Saturday. The officials spoke on condition of anonymity because they weren't authorized to release the information.

— Police found the bodies of four men who had been abducted a week ago chopped into pieces in Dujail, 80 kilometers (50 miles) north of Baghdad.

— A roadside bomb killed one civilian and wounded another while they were driving on the highway south of Baghdad.