Afghanistan suicide bomber infiltrates Kabul police HQ

The police headquarters is supposed to be one of the most secure areas of Kabul

Afghan authorities are investigating how a suicide bomber was able to enter the offices of the Kabul police chief and kill a senior officer.

Police chief Zahir Zahir was not in his office at the time of the attack, but he said his Chief of Staff Yassin Khan was killed and six others wounded.

The incident took place in one of the most fortified areas of the capital.

Kabul is regularly subjected to Taliban bombings, with the military, police and government officials all targeted.

Questions are being asked as to how the bomber was able to evade heavy security at the police base