The Interior Ministry’s spokesman says security forces are trying to clear the building.
The attack started at 11:40am Kabul time with an explosion outside the entrance gate of Counterpart International, an international organization which is operating in Afghanistan since 2005, and was followed by gunfight as other attackers tried to enter the building, according to Nusrat Rahimi, a spokesman for Ministry of Interior Affairs.
Rahimi said security forces have surrounded the attackers and that gunfire is still ongoing in the area.
Wahid Mayar, spokesman for Ministry of Public Health, said at least nine wounded were taken to hospitals following the attack.
Sporadic gunfire is still heard from the attack scene Kabul police spokesman Basir Mujahid said, adding that the exact number of the attackers is not clear so far.
Ambulances, firefighters and military vehicles were seen near the attack scene.
The security forces seized an explosive-laden vehicle from the attackers and rescued more than 150 employees of the Counterpart International.
Taliban in a statement claimed responsibility for the attack.