BAGHDAD - Iraq's Shiite prime minister exchanged heated words with a Sunni Arab lawmaker yesterday over the country's new security plan, leading parliament temporarily to suspend a raucous debate and Iraqi television to abort its coverage.

The dispute underscored the deep divides that have bedeviled attempts to quell Iraq's sectarian conflict.

As the legislators debated, the violence here continued. More than 80 Iraqis and at least one U.S. soldier were reported killed in a string of bombings, mortar fire and other bloodshed.

In the day's worst attack, a suicide car bomber caused a huge explosion at a busy intersection in Baghdad's mostly Shiite Karradah neighborhood, where shoppers waited to buy bread outside a bakery, killing at least 27 people and injuring 54, police and witnesses said.

"These terrorists are always one step ahead of the government security forces," said Ridha Mustapha, a minibus driver who rushed to the scene after hearing the blast from his apartment. "It should be the other way around. All the government does is talk about the security plan, when the fact of the matter is that they should be taking the initiative in order to deter these attacks before they even occur."

The parliamentary clash took place as Prime Minister Nouri al-Maliki presented his arguments in favor of the U.S.-backed security plan, which he named "Operation Imposing Law." The plan would leave no safe havens for armed extremists, regardless of religious or political affiliations, he told lawmakers.

"Some say that this plan targets Sunnis or Shiites," Maliki said. "The fact is that this plan targets all who stand in the way of the law."

Abdul Nasir al-Janabi, a Sunni cleric and legislator from a region south of Baghdad notorious as the Triangle of Death, responded by protesting a major sweep by U.S. and Iraqi troops Wednesday through Haifa Street, a Sunni neighborhood of the capital that is dominated by antigovernment extremists. Sporadic blasts continued yesterday in the area, where more than 30 gunmen have been killed, according to Iraqi officials.

Janabi accused Maliki's administration of purging Sunni Arabs from the government, arresting pilgrims returning from Saudi Arabia, and imposing politically motivated death sentences, a possible reference to Saddam Hussein's execution last month.

"We cannot trust this premiership," Janabi said, as the shouting escalated around him.

Maliki retorted: "All I could tell our brother the sheikh is that he will trust in this premiership once we present his file and hold him accountable for it."

As Shiite legislators loudly applauded, he added: "One hundred and fifty kidnapped individuals in his area - why doesn't he talk about that?"

Mahmoud Mashhadani, parliament's speaker and a Sunni, interrupted the exchange, chiding Maliki for making "unacceptable" accusations and adding with heavy sarcasm that "the security plan will be very successful because you people are divided from this moment."

He then called for an adjournment to avoid inflaming sectarian tensions. The session resumed soon afterward, but Iraqiya, the state-run television station, stopped airing it. The station later put out an edited version of events.

The early-evening explosion in the upscale Karradah neighborhood torched dozens of shops and apartments, littering the streets with body parts and debris.

"I don't know the fate of many of my friends and relatives," said Maan Abid, who saw the blast from his plumbing store. ". . . There are numerous charred bodies. The only thing that saved me was the wall that I was standing next to, right outside my shop. Otherwise, the shop is destroyed, all the windows shattered."

Witnesses said the suicide bomber tried to park his sport-utility vehicle at the intersection but blew himself up when traffic police ordered him to move on. At least two policemen were among the 27 people killed.