Sporadic clashes broke out Tuesday between gunmen and Iraqi security forces in a Sunni Arab district of northern Baghdad as soldiers sealed off streets and manned checkpoints a day after a major gunbattle there.

Residents of Azamiyah began trickling out of their homes late Tuesday after spending nearly two days holed up inside. Some shops also reopened.

Elsewhere in the capital, a bomb exploded at a cafe frequented by police in the eastern neighborhood of Suleikh, killing at least three policemen and four civilians and wounding more than 20 other people, police said.

The bomb was hidden underneath a couch at the entrance to the cafe, police Capt. Ali al-Obeidi said. Tables and chairs were thrown from the building in the blast, and glass windows of nearby shops were broken.

Tuesday's clashes in Azamiyah left two gunmen dead and six people, including civilians, wounded. The U.S. military said at least five insurgents were killed and two Iraqi troops wounded in fighting Monday.

U.S. officials referred to the gunmen as insurgents. But some residents said they were simply neighborhood men who feared that the Iraqi troops were working with Shiite death squads who had come to kidnap and kill Sunnis.

Residents, who spoke on condition of anonymity for fear of reprisals, said gunmen went from house to house, urging families to provide male members to help them defend the neighborhood.

That illustrates the depth of the sectarian crisis facing Iraq and the deep suspicions with which many Sunni Arabs view the government's Shiite and Kurdish-dominated security forces.

Sunni leaders echoed the charges, blaming the Shiite-dominated government for the violence. They accused Shiite militias and government forces of taking advantage of the current power vacuum to step up "ethnic cleansing" in predominantly Sunni neighborhoods in Baghdad.

Sunni lawmaker Adnan al-Dulaimi said Tuesday in a statement that a campaign of intimidation was in full swing in the Baghdad areas of Azamiyah, Abu Ghraib and Dora, adding that this is "proof of the ugly cooperation between the government security bodies and the bloody militias against the citizens."

Al-Dulaimi blamed the deteriorating security situation on "the existence of unleashed militia, including some militia backed by foreign powers who have only one goal — that is to see Iraqis slaughtered in a sectarian war."

The Iraqi Front for National Dialogue, led by Sunni politician Saleh al-Mutlaq, also demanded that government officials "stop their raiding, kidnapping and looting operations in Azamiyah."

Anger by the Sunnis comes at a time of acute political instability as the nation's different ethnic and religious factions struggle to form a government of national unity. Talks have been stalled for months over the issue of who should be the country's next prime minister, with the Sunnis and Kurds steadfastly rejecting the Shiite nomination of incumbent Ibrahim al-Jaafari.

Al-Jaafari has refused to give up the nomination that he narrowly won in a Shiite caucus last February. Shiite leaders met Tuesday to discuss the possibility of a new Shiite candidate, but prospects for a quick end to the stalemate were in doubt as al-Jaafari's Dawa party pledged to support him for a second term.

Parliament had been set to meet Monday to try to break the deadlock, but the session was postponed after Shiite politicians gave assurances they could reach a decision on al-Jaafari themselves without a bruising parliamentary fight.

No major violence was reported Tuesday in Ramadi, a day after U.S. troops repelled a major assault by Sunni insurgents against the city's main government building and two U.S. observation posts.

The U.S. military also said Tuesday that a suicide car bomber attacked Iraqi security forces the day before at a checkpoint south of Rawah, in the volatile Anbar province, killing one Iraqi soldier and wounding another.

In the Dora district of southern Baghdad, police discovered two bodies, both shot in the head, on Tuesday. Twelve other bodies were found in the same neighborhood on Monday.

In a drive-by shooting, assailants gunned down a police officer walking near his home in the southern city of Basra, police said.

Sectarian violence exploded in Iraq after the Feb. 22 bombing of a major Shiite shrine in Samarra, prompting a wave of reprisal attacks against Sunnis.

Attacks on politicians also are on the rise.

The body of Taha al-Mutlaq, the brother of the Sunni leader of the Iraqi Front for National Dialogue, was discovered Monday in a Shiite area of western Baghdad. He had disappeared last month en route to Salahuddin province north of Baghdad.

Saleh al-Mutlaq said the motive of his brother's killing was political.

"This criminal act wasn't done for money, or for revenge, because Taha has no enemies," al-Mutlaq said Tuesday at a news conference. "It was political — they are targeting any project that aims to unite Iraq."