Kabul, Aug 22 (IANS): The US has warned its citizens to avoid the Kabul airport amid concerns about the potential for attacks by Afghanistan's branch of the Islamic State (IS) terror group, the BBC reported.

A security alert on Saturday told US citizens to stay away due to possible "security threats outside the gates".

Only those individually told to make the journey by a US government representative should do so, it said.

US defence officials said they were monitoring developments and looking at alternative routes.

No further details were given about the potential threat of an IS attack, and the group has not publicly threatened to carry out attacks in Kabul.

The US advice on Saturday came amid continued chaos outside the airport terminal and reports of people being crushed as thousands attempt to escape from Afghanistan following the Taliban takeover.

The militant group swept across the country and captured the capital, Kabul, a week ago.

Crowds have been gathering daily, hoping to be allowed on to a flight.

Those who work with the US and its allies, as well as people who have campaigned on issues like human rights, fear they may face reprisals at the hands of the Taliban if they are unable to leave.