Taliban claims responsibility for Afghanistan attack that kills at least 7

Two suicide bombers in the Afghan capital targeted two buses carrying Afghan army troops on Wednesday, killing seven and wounding 21 people, police said.

The bombings, for which the Taliban claimed responsibility, came a day after Afghanistan and the United States signed a security pact allowing U.S. forces to remain in the country past the end of the year to support Afghans as they take over the fight against the Taliban insurgency.

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The first attacker hit a bus with Afghan National Army officers, killing seven and wounding 15 in west Kabul, said the city's criminal investigation police chief Mohammad Farid Afzali.

The second attacker, who was also on foot, blew himself up in front of a bus in northeastern Kabul, wounding several army personnel, Afzali said.

Taliban spokesman Zabihullah Mujahid claimed responsibility for the attacks.

Under the security pact, along with a separate deal signed with NATO, about 10,000 American troops and several thousand more from other NATO countries will stay to train and advise Afghan forces after the international combat mission ends on Dec. 31.

More than a decade after U.S. forces helped topple the Taliban in the wake of the Sept. 11 attacks, Afghanistan is still at war with the Islamic militant group, which regularly carries out attacks, mainly targeting security forces.

There are also serious questions about the ability of the Afghan security forces to take on the militants, even with a residual U.S. force remaining in the country.

The pact was long in the making. U.S. officials had first warned their Afghan counterparts that if the security accord was not signed by the end of 2013, the Pentagon would have to start planning for a full withdrawal of troops from Afghanistan.

But when the year ended, the White House moved back the deadline, saying then-President Hamid Karzai needed to sign off within weeks. Karzai surprised U.S. officials by ultimately saying he would not sign the accord and would instead leave that task for his successor.

But the results of the race to replace Karzai took months resolve, finally coming to a conclusion on Monday with the swearing in of Ashraf Ghani Ahmadzai as Afghanistan's second elected president.

Ahmadzai signed the security agreement Tuesday, nearly one year after the White House's initial deadline.