Two explosions rocked Kabul at about 2.30pm local time on Monday.
Early reports indicate both explosions were in the vicinity of the Ministry of Defense in PD2, Murad Khani area in downtown Kabul.
Unconfirmed reports state initial blast was followed by a second bombing after people responded to the first explosion.
Eyewitnesses have said dozens of people injured in the attack.
The Taliban has claimed responsibility.