A firefight erupted at Kabul airport on Monday when Afghan guards exchanged fire with unidentified gunmen and one guard was killed during the clash, which involved US and German soldiers, Germany's military said.
Thousands of Afghans and foreigners have been thronging the airport for days, hoping to catch a flight out after Taliban fighters captured Kabul on August 15.
Twenty people have been killed in the chaos at the airport, most in shootings and stampedes, as US and international forces try to evacuate citizens and vulnerable Afghans.
CNN said the clash began when a sniper outside the airport fired at Afghan guards, who are mostly former government soldiers helping US forces, near the airport's north gate.
US and German forces were involved in the clash, Germany's military said.
Three Afghan guards were being treated at a field hospital in the airport, it said.
Two NATO officials at the airport said the situation was under control after the firing.
The Taliban have deployed fighters outside the airport, where they have tried to help enforce some kind of order.
On Sunday, Taliban fighters beat back crowds at the airport a day after seven Afghans were killed in a crush at the gates as the deadline for the withdrawal of foreign troops approaches.
Foreign forces in Afghanistan have not sought to extend the August 31 deadline to leave, a Taliban leadership official said, adding it would not be extended, after President Joe Biden said US troops might stay longer to oversee a "hard and painful" evacuation.
The Taliban seized power just over a week ago as the United States and its allies withdrew troops after a 20-year war launched in the weeks after the September 11, 2001, attacks as US forces hunted al Qaeda leaders and sought to punish their Taliban hosts.
The administration of Biden's predecessor, Donald Trump, struck a deal with the Taliban last year allowing the United Sates to withdraw its forces in exchange for Taliban security guarantees.
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