A homicide car bomber hit a convoy of security contractors in the Afghan capital Thursday, killing an American and a Nepalese citizen and wounding three other Americans, police said. The Taliban claimed responsibility.

Two Afghan civilians were wounded in the attack in eastern Kabul, said Najibullah Samsur, a local police chief.

"There were two foreigner vehicles that passed near my shop and a third private vehicle hit them, causing the explosion," said Ahmad Shah, whose shop is close to the blast site.

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He said the attacker's vehicle and two of the contractors' vehicles caught fire after the explosion.

The foreigners from one of the vehicles that was lightly damaged fired their guns into the air to prevent civilians from approaching, Shah said.

Zabiullah Mujaheed, a purported Taliban spokesman, said the militant group was behind the blast.

Elsewhere, Taliban militants released 17 Afghan deminers kidnapped last week in Ghazni province, said Kazim Alayar, the province's deputy governor. Seven were released on Wednesday and 10 on Thursday, he said.

The men disappeared last Friday in Ghazni's Andar district. They were freed with the help of the local elders, Alayar said.

Afghanistan is one of the world's most heavily mined countries following three decades of war, and the U.N. and other aid groups are working all over the country to clear old minefields.

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