The Ministry of the Interior said six people were killed and five others wounded in Saturday's attack in the diplomatic quarter of the capital.

A senior police official speaking off the record to the AFP news agency said the suicide bombing was carried out by a teenage boy and that the victims included several children who sold small items to ISAF soldiers entering or leaving NATO headquarters.

The Kabul police chief, General Ayub Salangi, confirmed only four deaths, but also said children were among the dead and wounded.

Police sealed off the area after the attack.

The Taliban has claimed responsibility for the attack, saying the CIA had been the target. The Islamist group has been leading a long-running insurgency against the US and the Afghan government.

A spokesman for the NATO-led International Security Assistance Force (ISAF) said there had been a blast outside headquarters, but that there had been no ISAF casualties.

The diplomatic quarter where the explosion occurred is home to many Western embassies, including that of the United States.

The attack took place as dignitaries gathered in Kabul to mark the 11th anniversary of the death of Ahmad Shah Massoud, the Northern Alliance commander killled in an al Qaeda suicide bombing two days before the September 11, 2001, attacks in the United States.

The Alliance joined with the United States in helping to oust the Taliban after the US invaded Afghanistan a month after the 9/11 attacks in New York and Washington.

tj/pfd (AFP, AP, dpa)