Gen. Abdul Razeq, one of Afghanistan's most powerful security officials, was killed on Thursday when a bodyguard opened fire following a meeting in the governor's compound in the southern province of Kandahar, officials said.

Gen. Scott Miller, the top US commander in Afghanistan who had been at the meeting with Razeq only moments earlier, was not injured in the attack. But the local commander of the NDS intelligence service and the Kandahar provincial governor Zalmay Wesa were also killed.

The Taliban claimed responsibility for the attack, saying they had targeted both Miller and Razeq, the police chief of Kandahar who had a fearsome reputation as a ruthless opponent of the insurgents in their southern Afghan heartlands.

The attack was a devastating blow to the Afghan government ahead of parliamentary elections on Saturday, which the Taliban have vowed to disrupt. The attack underlined how precarious the situation remains in Afghanistan even after Taliban and US officials had opened preliminary contacts aimed at establishing the basis for future peace talks.

Officials said Razeq, Miller and the other officials were walking towards a landing zone as the helicopter taking the US general’s party back to Kabul approached to land when the gunman, who was waiting outside, opened fire on the group.

At least two hand grenade explosions and sporadic gunfire from around the compound were also reported by officials.

Local officials said Miller appeared to have been saved by his body armour but there was no immediate confirmation from Nato headquarters.

“The brutal police chief of Kandahar has been killed along several other officials,” a Taliban statement said.

Razeq was criticised by human rights groups but highly respected by US officers who saw him as one of Afghanistan’s most effective leaders, largely responsible for keeping Kandahar province under control.

The flamboyant commander, whose men wore badges bearing his name, had survived several attempts on his life over many years.