Frantic Afghans trying to flee the Taliban takeover clung to an American plane as it prepared to take off from Kabul airport, as thousands of people desperately searched for a flight out of the country on Monday.

US troops fired shots into the air and all commercial flights were cancelled as chaos broke out on the tarmac.

Dramatic footage posted on social media shows hundreds of men running alongside a US Air Force plane as it rolls down the runway, with some clinging to the side of it.

In other videos, civilians frantically clamber up an already overcrowded and buckling set of airstairs.

Crowds watched on, as those who successfully climbed the stairs helped others up, while some hung from the stair railings by their hands.

Panicked families with frightened children in tow and laden with luggage were trying to escape the incoming Taliban regime, two decades after the group’s harsh rule was toppled by a US-led invasion.

“I feel very scared here. They are firing lots of shots into the air,” the witness said, asking not to be named in case it jeopardised his chances of leaving.

The US State Department said American troops had secured the perimeter of the airport as they evacuate embassy employees and thousands of Afghans who worked for Washington’s interests since they toppled the Taliban in the wake of the September 11 attacks.

The scenes at the airport were reminiscent of the chaos that enveloped Washington’s earlier bungled escape from Vietnam in 1975, even as US Secretary of State Antony Blinken rejected the comparison.

'We are afraid’

The US embassy in Kabul tweeted to tell American nationals and Afghans to “not travel to the airport”.

But thousands more Afghans — even some with no links to the US-led coalition — showed up in the hope of getting out, without tickets or visas for foreign destinations.

The bedlam at the airport came just hours after Taliban leaders ordered their fighters into Kabul to maintain order as Afghan President Ashraf Ghani fled the country.

“We are afraid to live in this city and we are trying to flee Kabul,” said a 25-year old man who also asked to be identified only as Ahmed.

Many of the arrivals were fuelled by rumours spread on social media.

“I read on Facebook that Canada is accepting asylum from Afghanistan,” said Ahmed.

“Since I served in the army… there is danger. The Taliban would definitely target me.”

The US said it had evacuated its entire embassy staff to the airport, but they were being kept separate from those without permission to travel.

Other videos posted on social media also showed desperate scenes overnight of people fighting to cram into the back of a cargo plane.

Outside of the airport, an uneasy calm held over Kabul as armed Taliban insurgents patrolled the streets and set up checkpoints.

In a message posted to social media, Taliban co-founder Abdul Ghani Baradar called on his fighters to remain disciplined after taking control of the city.

“Now it’s time to test and prove, now we have to show that we can serve our nation and ensure security and comfort of life,” he said.

The scenes at the airport were reminiscent of the chaos that enveloped Washington’s earlier bungled escape from Vietnam in 1975, even as Washington swatted away the comparison.

“This is not Saigon,” US Secretary of State Antony Blinken told a broadcaster on Sunday. (AFP)

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