He was a barber named Jabbar. His customers could count on finding him in his simple shop on Rasheed Street, a bustling commercial strip in the center of the city.

Jabbar was clipping hair as usual on Tuesday morning with his 10-year-old nephew, Nazar, helping out when a single mortar shell exploded on the sidewalk outside. It made just a tiny hole in the concrete but killed seven people, including Jabbar, Nazar and two people who had come in for a trim. Another 47 people were wounded, according to the Health Ministry. All the victims were civilians.

The shell detonated while Iraq's U.S.-supported interim government was assembling a delegation to send to the southern city of Najaf in an attempt to end a deadly uprising against U.S. troops by the militia of Shiite Muslim cleric Moqtada Sadr.

But many Iraqis say the bigger threat to the infant government is the kind of violence that mauled Rasheed Street on Tuesday -- bullets and explosions that in a flash take the lives of ordinary people who happen to be on the scene.

"This is a cowardly act performed by the groups which want to destroy Iraq," said Sabah Kadhim, a spokesman for the Interior Ministry. "Regretfully, the security situation is difficult, and it is one of our concerns. But the police and the security forces are trying their best to control the situation. The government is insistent to fight those terrorists."

But people who lingered on the street after the explosion Tuesday took a different view. "This is an American war," said a woman who gave her name as Um Zamen. "They do all this violence and kill the Iraqi people."

Hundreds of people have died in recent months in similar attacks, which usually target institutions of the new government and the foreign soldiers who last year overthrew the government of Saddam Hussein.

Elsewhere in the city Tuesday, two blasts shook the Baghdad convention center, where more than 1,100 Iraqis are meeting to select an interim assembly that will help lead the government until elections are held next year, the Associated Press reported. A soldier and a civilian security guard were slightly injured, the military said. In Anbar province, west of Baghdad, one Marine was killed Tuesday, and the military reported the death Monday of a soldier in eastern Baghdad, in a bomb and rocket-propelled grenade attack.

As blasts go, the one on Rasheed Street was not one of the deadliest.

That mattered little to the family of Jabbar and Nazar, who rushed to the Medical City hospital, where they were told that the two were dead. Nazar's father, mother and brother crouched in separate corners, unable to repress their loud cries and weeping. "I want my brother. I want my brother," a small boy, dirty and barefoot, wailed from the cool white tile floor of the hospital waiting room. His nose ran as he cried into his hands.

His father sat on a bench nearby, also crying and wringing his hands. The dead boy's mother slumped on the floor and ripped her black abaya, the long, loose-fitting robe worn by Muslim women. With a shaking brown hand, she batted away anyone who tried to comfort her.

The barbershop was one of 10 businesses destroyed by the mortar shell, which hit at around 11:30 a.m. when the area was filled with people running errands before the afternoon sun blazed too hot and sent them inside. The blast sparked fires that raced through the shops.

About an hour later, smoke still rose from the cindered floor of the barbershop. A black chair, remarkably, remained intact on its swiveling metal pole. The fake leather upholstery was smeared with blood.

Why the shell hit here was not clear. Jamal Abdullah, an Iraqi police officer who had rushed to the scene, said a U.S. military patrol had passed by about 10 minutes before the explosion. But he could offer no other explanation.

Luay Afeef, 43, his clothes torn and dirty, was inside his television repair shop next to the barbershop when the shell exploded. "I fix broken TVs -- that's all," said Afeef, who rubbed at his ears, still ringing from the blast. "I never work with the government or with the Americans."

Afeef said he was friends with Jabbar. When he tried to talk about the barber, he broke down in tears. "I lost him. I lost him," he repeated, his voice choked with grief.

Abdullah Bader, 51, said he had come to Rasheed Street to get some tools for his office. He and the director of a state-owned electrical company where they both work were unharmed, but Bader's car was destroyed.

"I just went to the market," he said. "That's all I did."

Um Zamen, whose broad nose and thin, pink lips showed from beneath a blue and black scarf, said most of the victims on Rasheed Street were poor.

"We just eat rice and bread," she said, taking in the scene of mangled metal and torched cars. "We are simple people here, and the Americans and the stupid government want to kill us. Saddam is gone, and now we have the casualties."

She had no use for the national conference or the political discussions within it. "Our government is just a fake," she said. "They don't want us to be happy and be normal."

While she spoke, Iraqi police arrested two looters who were picking through the debris of the burned-out businesses.

Special correspondent Bassam Sebti contributed to this report.

Charred vehicles litter Rasheed Street in central Baghdad after a mortar shell exploded, killing seven civilians.