Sediq Sediqqi, spokesman for the Afghan interior ministry, blamed the blast on the Haqqani Network faction of the Taliban, which has been held responsible for a string of suicide bombings and assaults on the capital.
The bombing came hours after the Pakistan-based network was designated a terrorist organisation by the American government. The classification will allow Washington to seize assets and block funding to the militant movement, which is considered the most sophisticated and dangerous arm of the insurgency.
Mr Sediqqi speculated the bombing was retaliation for the blacklisting.
The international military coalition condemned the attack.
Brig Gen. Günter Katz, a Nato spokesman, said: "If these reports are true, by taking advantage of an impressionable child to carry out this attack, the insurgents display cowardice.
"Forcing underage youth to do their dirty work again proves the insurgency's despicable tactics. They are completely detached from Afghan society and the interests of the Afghan people who desire peace and stability in their country."
Zabiullah Mujahid, a spokesman for the Taliban, said the attack had been carried out by a 28-year-old from Logar province. He said it had targeted a CIA torture centre and killed and wounded a number of American agents.
The blasts came as Afghanistan held a national holiday to mark the 11th anniversary of the death of Ahmad Shah Massoud, a Mujahideen resistance leader who went on to fight the Taliban and was eventually assassinated by an al Qaeda suicide bomber.
The holiday was marred by clashes in Western Kabul between supporters of Massoud and residents in the Pul-e-Surkh neighbourhood. Gen Daud said one policeman was killed in the clashes and one wounded.
The bombing came hours after the Pakistan-based network was designated a terrorist organisation by the American government. The classification will allow Washington to seize assets and block funding to the militant movement, which is considered the most sophisticated and dangerous arm of the insurgency.
Mr Sediqqi speculated the bombing was retaliation for the blacklisting.
The international military coalition condemned the attack.
Brig Gen. Günter Katz, a Nato spokesman, said: "If these reports are true, by taking advantage of an impressionable child to carry out this attack, the insurgents display cowardice.
"Forcing underage youth to do their dirty work again proves the insurgency's despicable tactics. They are completely detached from Afghan society and the interests of the Afghan people who desire peace and stability in their country."
Zabiullah Mujahid, a spokesman for the Taliban, said the attack had been carried out by a 28-year-old from Logar province. He said it had targeted a CIA torture centre and killed and wounded a number of American agents.
The blasts came as Afghanistan held a national holiday to mark the 11th anniversary of the death of Ahmad Shah Massoud, a Mujahideen resistance leader who went on to fight the Taliban and was eventually assassinated by an al Qaeda suicide bomber.
The holiday was marred by clashes in Western Kabul between supporters of Massoud and residents in the Pul-e-Surkh neighbourhood. Gen Daud said one policeman was killed in the clashes and one wounded.