The US embassy in Afghanistan has advised American citizens to avoid traveling to Kabul’s airport due to “potential security threats”.

Sky’s chief correspondent Stuart Ramsay is there and reports on what he saw on Saturday morning as thousands of people wait to get inside to be evacuated.

The mornings are always challenging on the barricades. The British soldiers know that after a night waiting for the evacuation process to restart the tens of thousands camped on the road leading to their base will try to rush their way through.

Today it was different. Very different.

Today it turned chaotic in an instant.

Within minutes this was an emergency, nothing to do with process; the soldiers found themselves just trying to save lives.

At the front of the queue people were being crushed to death.

Paratroopers began pulling people from the mayhem, medics rushing from the next casualty to the next, then the next and the next.

Crushed, dehydrated, terrified.

Standing on top of the compound wall, soldiers sprayed the crowd with a hose – anything to cool them down.

We saw men, women, and lots and lots of children.

And then what we had all feared began to happen.

Soldiers started shouting for medics and stretchers as unconscious people were carried to the rear. The medics checked their vital signs and then covered the bodies in white sheets.

“Is this a stabilised withdrawal from Afghanistan?” I thought.

It looks like death to me, death trying to reach freedom.

In the mayhem, units rush through crowds to shore up weak points in the evacuation centre – everyone working flat out trying to stem the tide of an unfolding disaster.

It doesn’t matter where you look it’s the same desperation – American soldiers, British soldiers, Spanish soldiers, German soldiers, Polish soldiers, pulling children, whole families from the pens and the crowds they’ve been kept behind for processing.

It feels like these people fear their dreams of a flight out are ebbing away as each day passes.

The soldiers sometimes have to fire in the air for fear of losing control of the crowd.

But it seems unlikely a gunshot is ever going to calm the frightened down.

This evacuation was predicated on Kabul remaining in the hands of the government, it was always going to be speedy and difficult, but the Taliban’s lightening takeover meant the planning was instantly out of date.

Looking back, putting the processing centre in place at the end of a long narrow street, publishing a press release saying the UK would take 20,000 Afghans without explicitly explaining it would be over the next 5 years, and then deploying a small group of soldiers given the job of processing people in the first instance while also maintaining military security – is morphing into a planning catastrophe.

If it’s to be turned around they’ll need more time but time is running out

Out here pain and compassion meet every minute of every day now.