KABUL, Afghanistan — In the capital's worst unrest since the fall of the Taliban 4 1/2 years ago, Afghan mobs fought running battles Monday with troops and police trying to quell riots sparked when U.S. military vehicles fled the scene of a fatal accident.
At least eight people were killed and more than 100 injured, most in the rioting that followed an early-morning traffic accident involving a convoy of U.S. military vehicles, Afghan officials said.
Rioters attacked the offices of the United Nations and foreign aid agencies, looting computers, books, desks and even shoes.
They also set fire to numerous police checkpoints across Kabul. As the mobs continued to run amok in midafternoon, a pall of smoke hung over some districts of the capital.
Protesters shouted, "Death to America!" and in a local epithet, "Death to Dog Washers!" They also condemned President Hamid Karzai and the former Afghan king, Mohammad Zaher Shah.
Karzai, in a nationally televised speech, described the rioters as agitators and "the enemy of Afghanistan" and urged Afghans to resist their efforts to foment violence.
"You should stand up against these agitators," the president said, "and not let them destroy our country again."
The government imposed a nighttime curfew. Yousuf Stanezai, an Interior Ministry spokesman, said all Kabul residents were to stay off the streets from 10 p.m. to 4 a.m. Anyone found outside would face "serious measures," he said.
Afghans often complain that U.S. military convoys drive recklessly, but the Americans say they drive aggressively to avoid threats such as roadside bombs and suicide attackers.
Afghan witnesses and the U.S. military gave conflicting accounts of what set off the riots.
Col. Tom Collins, a spokesman for the U.S. military in Afghanistan, called the accident "tragic" and "very regrettable" but said it was apparently the result of a "mechanical failure."
As the U.S. convoy was heading through Kabul about 8 a.m. Monday, a large cargo truck struck as many as 12 civilian vehicles, Collins said in a statement.
At least one Afghan was killed and six injured in the accident, he said. Afghan police said three people died and more than a dozen were injured.
According to Afghans, vehicles in the convoy rammed into about a dozen vehicles in the Zer-i-Kotal area, where used-car sellers operate a market on Kabul's northern edge.
The convoy then sped off into Kabul, but about a mile from the first incident hundreds of angry Afghans, many of them shopkeepers and taxi drivers, blocked the military vehicles in the Sarai Shamali district, the witnesses said.
Shopkeeper Ghulam Rauf said he was chatting when he saw the convoy of about half a dozen vehicles speeding toward a taxi that crossed in front of them.
"As the first vehicle crashed into the taxi, two other [American] vehicles started hitting other cars on the sides of the road," he said. "They destroyed all the vehicles that were standing there.
"And the soldier sitting on top was dancing and singing and shouting. Then they drove toward shops and into mobs of people standing there. They drove over them, and I saw people shouting, 'Help!' because their legs were cut open as the vehicles drove onto them."
Several shops were ruined, and as Afghans crowded in and tried to prevent the convoy from leaving, some of the vehicles opened fire with heavy weapons mounted on the roofs, Rauf and other witnesses said.
U.S. soldiers immediately provided medical aid to the injured, and Afghan national security forces came to the scene, Collins said.
"When the gathering crowd became hostile, the coalition vehicles attempted to move out of the area to reduce tensions," he said. "A second military convoy came to help the first convoy, and they departed the area, taking the damaged vehicle with them. Afghan security forces remained to handle crowd control."
Witnesses said U.S. troops and Afghan security forces fired on the crowd as protesters hurled rocks and fired guns. But it was not clear who fired the first rounds.
"There are indications that at least one coalition military vehicle fired warning shots over the crowd," Collins said. "We will determine the facts regarding the incident and cooperate fully with Afghan authorities."
Also Monday, officials said, five Canadian soldiers were hurt and as many as six militants were killed in a gun battle in Kandahar in the south, and U.S.-led coalition aircraft bombed suspected Taliban militants meeting in a remote southern area, reportedly killing dozens.
The Canadian soldiers were on a patrol about 15 miles west of Kandahar when they were ambushed, said Maj. Mario Couture, a coalition spokesman. Five soldiers were wounded, including one who received serious injuries and was flown to Germany for treatment, he said.
The body of a militant was left behind by his comrades and as many as five corpses were believed to have been taken away, he said.
Coalition warplanes bombed a Taliban compound in the village of Kajaki Sofla, in Helmand province, about 8 p.m. Sunday, the military said Monday.
Special correspondent Zaman reported from Kabul and Times staff writer Watson from New Delhi.