Kabul, Sep 29 : At least 27 people were killed and several others were injured when a suicide bomber boarded a crowded army bus here and detonated a huge bomb, officials said.

A high-ranking Afghan army medical official said 27 bodies had been taken to two hospitals.

Witnesses said that the bus was destroyed by the blast and several dead bodies can be seen around the wreckage.

The bus was completely destroyed by the blast and shop windows were shattered all around.

The explosion was caused by a suicide bomb attack, although this could not be immediately confirmed, officials said.

An Afghan military spokesman told the BBC that 21 people were injured in the bus blast.

He described it as an attack on the Afghan National Army.

The head of the Kabul Police, General Alishah Paktiawal, said the bomb went off at 0630 (0230 GMT) on board a bus packed with army staff.

It is still not clear whether a suicide bomber got on the vehicle before detonating his explosives or whether the device had been planted on or near the bus before it began its morning run.

In June, a police bus was targeted in Kabul, killing 35 officers in the worst attack in the city since the fall of the Taliban in 2001. (With inputs from ANI)