The moment that Westminster Bridge terrorist Khalid Masood was wheeled into hospital after killing five innocent victims has been shown for the first time.
Khalid Masood was the first person to be wheeled into St Mary's Hospital, in Paddington, after he carried out the atrocity.
Footage from BBC show Hospital, which follows some of the victims from the terror attack, shows hospital staff rushing to try to save the terrorist.
The camera crew were just two or three days into recording the new series, which follows the Imperial College Healthcare Trust, when a meeting being filmed at St Mary's was interrupted by news of the attack.
As Masood is brought in, an armed police officer tells the cameraman: "You can't film this, mate. It's a counter-terrorism incident, sir."
His blood-soaked stretcher is also shown, as hospital staff frantically discuss tactics of how to save him.
As his corpse is wheeled into another room, the doctor tells a police officer: "It's a formed area with just one door, so you guys can guard it, much easier for yourselves".
The extraordinary documentary, filmed in London hospital, shows victims being treated and discussing what they remember during the terrorist attack, which took place on March 22.
Five people died in the rampage, which saw Masood drive at pedestrians on Westminster Bridge before fatally stabbing Pc Keith Palmer in the grounds of the Palace of Westminster.
The 52-year-old attacker was then shot by armed police and was the first casualty to arrive at St Mary's Hospital in Paddington, where he was pronounced dead.
The episode also tracks the progress of three people injured during the attack - two French teenagers on a school trip, and a 40-year-old British man who was on a birthday excursion in the capital.
Simon Dickson of programme maker Label1, said of the decision to include the attacker: "He's part of the story, and his appearance in the film is as you see it.
"It's brief, but his arrival is a key part of the day, and that is fully reflected in the way that scene is handled."
Masood's family were not consulted about showing him, and his face is blurred out in the footage.
BBC Two controller Patrick Holland said: "The decision was made to treat him in exactly the same way, from the point of view of the hospital.
"That's where we're seeing him, that's where the audience is being allowed to see this incident unfold, he's the first casualty that comes to the hospital and we followed the same protocol that we do with any other patient which is that if they don't consent, you blur them."
Staff at the hospital, one of London's 'major trauma centres', are seen quickly putting a major incident plan into place as they prepare to receive the first casualties. All non-emergency surgery was cancelled, and doctors had to decide which existing patients are well enough to be transferred to another hospital to free up beds.
Dr Alison Sanders, clinical director at Imperial College Healthcare NHS Trust, said: "When a major incident happens, within 12 minutes the entire hospital has kicked into a completely different way of working, and obviously, subsequently we've had to do that twice more since this programme was made (with the London Bridge attack and the Grenfell Tower fire).
"It just demonstrates, that's something that won't be unique to us, it's a countrywide ability of the NHS to step up on top of what is already huge pressure."
She added: "We have to do something entirely different with zero notice, and you see everybody just switch into it, and then the following day we have to go back to normal because the work is still building up, the ambulances will still be coming in, as soon as we open the doors again, the floodgates open."