A suicide car bomb exploded near the main gate of the NATO-led international military mission Saturday, killing three Afghans and wounding 70, officials said. The Taliban claimed responsibility.

The pinpoint attack penetrated a heavily guarded neighborhood that also houses the U.S. Embassy and Afghan presidential palace just five days before Afghanistan's nationwide elections.

Bloodied and dazed Afghans wandered the street after the blast, and children _ many of whom congregate outside the NATO gate to sell gum to Westerners _ were among the wounded. Windows of nearby antique shops were shattered and blood smeared the ground.

Gen. Mohammad Zahir Azimi, the spokesman for the Afghan Ministry of Defense, said three Afghan civilians were killed and 70 wounded in the blast. Capt. Elizabeth Mathias, a U.S. spokeswoman for the NATO-led mission, said the explosion occurred near the gate of NATO's International Security Assistance Force. She had no immediate information on damage to the headquarters.

"I was drinking tea in our office when a big explosion happened," said Abdul Fahim, an Afghan in his mid-20s who sustained leg injuries. "I lay on the ground and then I saw wounded victims everywhere, including police and civilians."

A Taliban spokesman, Zabiullah Mujahid, claimed responsibility for the blast and said the bomb contained 1,100 pounds (500 kilograms) of explosives. Mujahid at first said the bomber was on foot, then later called back and said it was a suicide car bomb attack.

NATO headquarters has several large, cement blocks and steel gates that prevent anyone from reaching the entrance, and the bomber was not able to breach those barriers. Afghanistan's Transportation Ministry lies across the street from NATO headquarters.

The bomber was able to evade several rings of Afghan police and detonate his explosives at the doorstep to the international military mission, an assault possibly aimed at sending a sign that the Taliban can attack anywhere it wants. The NATO mission _ where top commander U.S. Gen. Stanley McChrystal works _ sits beside the U.S. Embassy and shares the same street as the presidential palace.

The blast _ before Afghans go to the polls this Thursday _ could also reinforce the Taliban's threat of violence to any Afghan who participates in the elections.

Afghanistan has braced for attacks because of the vote. International workers in the country were planning on working from home over the next week or had been encouraged to leave the country.

The blast rattled the capital and sent a black plume of smoke skyward. It was the first major attack in Kabul since February, when eight Taliban militants attacked three government buildings simultaneously, an assault that killed 20 people and the eight attackers.

Mujahid, the Taliban spokesman, said a suicide bomber named Ahmad carried out Saturday's attack.

A driver from the nearby Defense Ministry said he took at least 12 people to the hospital. Most were seriously wounded, said the driver, who spoke to an Associated Press reporter at the scene but didn't want to give his name because of safety concerns.

Kabul has been relatively quiet over the last half year, though militants have launched a barrage of rockets into the capital this month, most of which landed harmlessly in open spaces.

Security has increased over the last several weeks in preparation for Thursday's vote.