The Biden administration has curtailed the number of flights to the United States for Afghans who worked alongside the US, as it prioritizes the evacuation of American personnel from the country, three sources familiar with the situation told CNN.

The last flight of Afghan Special Immigrant Visa (SIV) applicants and their families bound for Fort Lee, Virginia, has left Afghanistan, four sources said.

One source said that the limitation on the number of flights that are able to transit in and out of the Kabul airport – which was a scene of mass panic and chaos on Sunday — has impeded efforts to evacuate the Afghans who worked alongside the US in its two-decade military campaign.

It is unclear how long the pause in inbound flights will last.