ABC News is reporting that the nine killed were Americans. Officials said it is the deadliest episode to date of an Afghan turning against his own coalition partners.
It happened in an operations room of the Afghan Air Corps at Kabul airport. According to officials, the Afghan officer, who was a veteran military pilot, fired on the foreigners after an argument.
"Suddenly, in the middle of the meeting, shooting started," said Afghan Air Corps spokesman Col. Bahader, who uses only one name. "After the shooting started, we saw a number of Afghan army officers and soldiers running out of the building. Some were even throwing themselves out of the windows to get away."
Five Afghan soldiers were also wounded in the incident. It was the seventh time so far this year that members of the Afghan security forces, or insurgents impersonating them, have killed coalition soldiers or members of the Afghan security forces.
Afghan President Hamid Karzai condemned the shooting and offered his condolences to the relatives of the victims. The president ordered his defense and security officials to investigate the recent incidents to determine why they occurred.
The Taliban claimed responsibility for the attack. In a statement, Taliban spokesman Zabiullah Mujahid said the gunman, who was killed during the shooting, was impersonating an army officer and that others at the facility helped him gain access.
However authorities have not confirmed any connection to insurgents. Defense Ministry spokesman Gen. Mohammad Zahir Azimi said the gunman was an Afghan military pilot of 20 years.
ABC News and The Associated Press contributed to this story