One British and one South African employee of the international courier company DHL, together with an Afghan guard, were killed in a shooting in the heart of the Afghan capital yesterday, officials said.
Police said they were questioning DHL employees but were not yet sure of the motive for the violence, which comes amid a rising tide of attacks and less than a week after Taliban militants killed a British aid worker in another part of Kabul.
"We can now confirm that a British and a South African national were killed in a shooting incident in Kabul," said a British Foreign Office spokeswoman. "We are in contact with the Afghan police to establish the circumstances."
Taliban insurgents have launched a number of attacks inside Kabul, but an Afghan Interior Ministry official said yesterday's shooting did not appear to be politically motivated.
"It was an encounter between Afghan guards and foreigners of the company," a ministry source said on condition of anonymity.
A spokesman for Deutsche Post, which owns DHL, confirmed the attack took place at about 8.30 a.m. local time outside the DHL offices in Kabul. The company was working with local authorities to find out what happened, he said.
If the Taliban do turn out to have been responsible for yesterday's attack, the hundreds of foreign aid workers in the city are likely to severely restrict their movements.
Police covered a silver sports utility vehicle at the scene with plastic sheeting. There was blood on the ground and two bulletholes in the window of the DHL office, which is close to the Iranian embassy and the headquarters of the national intelligence agency.
Kabul has seen a spate of killings and kidnappings in the last two weeks since President Hamid Karzai appointed a new interior minister in an effort to clean up widespread corruption at the ministry which controls the police force.
British aid worker Gayle Williams, gunned down by Taliban militants in Kabul, "gave her life serving the Afghan people she loved", her sister told reporters.
"Gayle was working to help little children with disabilities ... Gayle was passionate about trying to help them," said Karen Williams. "I know Gayle would forgive those responsible for this act and she would tell us not to hold a grudge against them."
The hardline Islamist Taliban said they had killed Gayle Williams because she worked for SERVE Afghanistan, which the militants said was promoting Christianity.
A spokeswoman for SERVE, a British-based Christian aid organisation, denied the claim.
"The Taliban has claimed that Gayle was targeted for promoting her faith. That is simply not true. Everyone in SERVE is here to do a professional job," said Rina van der Ende.