At least 21 people have been killed and 45 wounded in twin bombings near the Afghan parliament in Kabul, a security official says.

Most of the dead were civilians, including parliament employees, the official told the AFP news agency.

The attack took place during rush hour, as staff were leaving the parliament complex.

Reports suggest a suicide bomber and a car bomb, but no group has yet claimed the attacks.

An injured parliament security guard named as Zabi told AFP: "The first explosion happened outside the parliament... a number of innocent workers were killed and wounded. It was caused by a suicide bomber on foot."

Describing the car bomb, the guard said: "It was parked on the other side of the road and flung me back when it detonated."