The attacker was targeting a convoy of foreign troops at the third gate, but it was not immediately known if there were any casualties. However, a security official who asked not to be identified said at least four Afghan civilians were killed in the suicide attack. He said the injured had been sent to the medical facility at the base.
The NATO Resolute Support Mission confirmed the attack in a statement and said the injured civilians were being treated at the hospital on the base.
The Taliban claimed credit for the attack that comes a day after the US military airdropped leaflets containing an image highly offensive to Muslims.
On Wednesday, the US army apologized for airdropping the leaflets.