A Briton has been shot dead by a guard in Afghanistan, the Foreign Office confirmed.

The employee of courier company DHL was killed at around 8.30am local time outside the firm's headquarters in Kabul, the company said.

He has been named as David Giles by the Foreign Office. Next of kin have been informed.

Another foreigner, believed to be South African, also died in the attack.

Officials said the men were director and deputy director for DHL in Afghanistan.

A spokesman for DHL said: "At this difficult time our thoughts are with the families, friends and colleagues of those who have lost their lives under such tragic circumstances."

He added: "DHL is fully co-operating with authorities investigating the incident. In order not to hinder the investigation no further information can be released at this time."

Mirza Mohammad Yarmal, the Interior Ministry official in charge of criminal investigations, said the guard, who was employed around a month ago, opened fire on the pair before turning the gun on himself.

Thirteen people have been arrested in connection with the shooting, the circumstances of which are not yet clear.

The Taliban has denied any involvement.

The attack follows the death of aid worker Gayle Williams, 34, who was gunned down on her way to work in the Afghan capital on Monday.

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