"We are facilitating safe-exit passage not just for foreigners but also to Afghans," the official told Reuters on Thursday.

"We are preventing any form of violent, verbal clash at the airport among Afghans, foreigners and Taliban members."

Flag-waving protesters took to the streets of more Afghan cities on Thursday as popular opposition to the Taliban takeover spread.

A witness said several people were killed when the militants fired on a crowd in Asadabad in the east.

Australian Associated Press