Video has been published online appearing to show civilians clinging on to an American aircraft leaving Afghanistan's Kabul Airport.
Senior US military officials say the chaos at the Kabul airport has left seven people dead, including some who fell from a departing American military transport jet.
The Taliban claimed control of the Afghan capital last week, and the UK has deployed hundreds of troops to help rescue UK nationals.
The United States has also been evacuating its citizens from the city.
The first Royal Air Force flight from Afghanistan carrying British nationals arrived overnight at RAF Brize Norton in Oxfordshire.