A suicide car bomber killed six Italian soldiers and 10 Afghan civilians Thursday in the heavily guarded capital of Kabul.
The Taliban claimed responsibility for the deadliest attack for the Italian contingent in the country.
Violence has increased since the U.S. sent thousands more troops to push back the resurgent Taliban and bolster security for last month's still-unresolved presidential election. The Taliban made good on threats to disturb the vote, and militant attacks have risen not just in the group's southern heartland but also in the north and in Kabul and surrounding areas.
The bomber rammed his explosives-filled car into two Italian military vehicles in a convoy about midday. Four Italian soldiers were also wounded, said Italian Defense Minister Ignazio La Russa. The Afghan Interior Ministry said an additional 55 civilians were injured.
The explosion shattered windows in buildings about half a mile away and shook offices and homes throughout the central Afghan neighborhood that houses embassies and military bases.
Charred vehicles littered the road just off a main traffic circle that leads to the airport. An Associated Press reporter saw six vehicles burned, including an Italian Humvee, and two bodies covered with plastic sheets.
Shopkeeper Feraudin Ansari said he felt the blast in his store about 50 yards away. Windows were broken in all the shops on the street. He said he was angry at NATO forces for being in the downtown area.
"Why are you patrolling inside the city? There is no al-Qaida, no Taliban here," said Ansari, 25. "My shop is destroyed, and my head hurts from the blast."
U.S. State Department spokesman Ian Kelly condemned the bombing and said that the attack "reinforces the need for the U.S. and allies, in partnership with the people of Afghanistan, to continue our critical work."
Elsewhere, a NATO service member died from a bomb strike in the south Wednesday, NATO forces said.
Election results disputed
In addition to violence, Afghanistan is mired in debates about the legitimacy of the fraud-tainted presidential balloting, whose uncertain result threatens to undermine the government's authority.
In his first public comments on the disputed election, President Hamid Karzai defended its integrity, saying Thursday he had seen only limited proof of fraud. Full preliminary results showed him with 54.6 percent of the vote, well ahead of leading challenger, former Foreign Minister Abdullah Abdullah. But recounts and fraud investigations could drive Karzai's total below 50 percent, forcing him into a runoff.
Acknowledging fraud, Karzai said "there were some government officials who were partial toward me," but he alleged that others had manipulated results to favor Abdullah.
"I believe firmly in the integrity of the election, in the integrity of the Afghan people and in the integrity of the government in that process," Karzai said.
On Wednesday, European election monitors said about a quarter of the 5.6 million votes cast Aug. 20 should have been set aside pending an investigation.
A U.N.-backed Electoral Complaints Commission, which is the final judge of the count, has ordered a recount of about 10 percent of polling stations countrywide because of suspect results. The complaints panel has thrown out results from 83 polling stations because of "clear and compelling" evidence of fraud.
Karzai, who spoke at his palace a few miles away from the blast site shortly before the explosion, said he had seen concrete evidence that 1,200 ballots were faked.
Opponent rules out coalition
Abdullah alleged "state-engineered fraud," and he urged Afghan and foreign officials to oppose the "corruption and malpractice" that he says marked the election.
"This is the wrong way forward for the future of this country," he said. "The champions out of this will be the Taliban."
Abdullah ruled out joining a coalition government, but said an "interim solution" — possibly a caretaker administration — would be needed if the ballot investigations drag on. Final results are unlikely for weeks.
The increased fighting and complaints about the election have raised questions abroad about whether the Afghan war is worth the cost in lives and financial support. Officials have said the war just needs to be refocused.
International forces are trying to refocus their tactics on protecting civilians rather than routing the Taliban. But that approach already derailed this month when a German-ordered airstrike on two hijacked fuel tankers killed civilians who had swarmed the vehicles to siphon fuel.
An Afghan commission investigating the incident gave its report Thursday to Karzai, saying 30 civilians and 69 militants were killed in the strike in northern Kunduz province. NATO said civilians died but has not said how many.
The German commander has said he ordered the bombing because he feared the hijacked trucks would be used for suicide bombings.
Karzai said that while Germany remained a "great friend" of Afghanistan, the strike was a mistake.
"The operation was wrong. It should not have been conducted. It could have been done through other means," he said.
Fourth major Kabul attack in five weeks
The Kabul attack was the fourth major strike in the capital in five weeks. A car bomb exploded near the military airport Sept. 8 in an attack on a NATO convoy that killed three civilians. The Taliban also claimed responsibility.
On Wednesday, U.S. Ambassador Karl Eikenberry took a public walk around a Kabul neighborhood, saying international officials need to spend less time behind blast walls and more time interacting with the people.
The commanding officer of U.S. and NATO forces in Afghanistan, Gen. Stanley McChrystal, has called for the military to be more engaged with the Afghan people to better protect them from the Taliban, and hopefully win their trust.
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