An Afghan army pilot who killed eight US troops and a civilian contractor had no links with the Taliban, NATO said in a statement on Saturday, DPA reported
"At this point in the investigation, it appears that the gunman was acting alone," it said.
"Beyond that, no Taliban connection with the gunman has been discovered; however, the investigation is still ongoing, and we have not conclusively ruled out that possibility."
Eight US troops and an American civilian contractor were killed on Wednesday when an Afghan army pilot opened fire on his foreign trainers at a Kabul airbase. The attacker, a veteran military pilot, was killed in the exchange of fire.
The shooting began after an argument between the pilot and foreign personnel inside the military airfield, adjacent to the capital's international airport.
The Taliban took responsibility for the attack, saying the shooter was a sleeper agent who used an Afghan army uniform and gained access to the military airport with the cooperation of an insider.
NATO said the gunman was severely wounded where the attack took place and was found dead at a different location in the building. He appeared to be carrying two weapons, the preliminary investigation found.