Police chief Gen. Mohammed Zahir told reporters before his resignation that the attack Saturday actually killed four people, raising the death toll in the assault near the Afghan parliament. He offered no other details about the victims and did not name the aid group.
A Redlands, California-based group called Partnership in Academics and Development later posted a notice on its website saying several of its staffers died during an attack Saturday in Kabul.
"We are caring for all staff and their families as they grieve the loss of their friends and co-workers and nurse the wounded," the statement read. "Our thoughts are with the survivors and their families as they grieve the loss of life. Their selfless sacrifice for the people of Afghanistan is an inspiration to all."
Clayson Monyela, a spokesman for South Africa's foreign affairs department, said Sunday that he had no information about the slain South Africans.
Saturday's attack saw three Taliban militants launch an assault on the office, with one exploding a suicide bomb vest. The two others were later killed in a shootout with police, authorities said. At least one of the attackers wore a police uniform, Zahir said.