A police officer and four attackers were among the dead after the standoff at the National Authority for Disabled People and Martyrs’ Families in Kabul, according to Najib Danish, an Interior Ministry spokesman.
The attack began Monday afternoon with the detonation of a vehicle bomb at the gates to the building, Danish said. Three gunmen then stormed the building, where hundreds were working.
More than 20 people, including two police officers, were wounded, the official said. At least 350 workers were evacuated and the number of casualties could rise, according to Danish.
Local authorities had earlier said the gunmen took hostages in the building.
The official said planning is underway, and it could take months to withdraw the nearly 7,000 troops.
Gen. John Allen, a former commander of NATO and US forces in Afghanistan, said Thursday that a drawdown in Afghanistan would be a mistake.