'That's it - the biggest disaster in the world, right there': Haunting footage of 9/11 captured by NYPD helicopter as towers fell

It is the most appalling attack of terrorism ever to hit America - as you have never seen it before.

A chilling new video has emerged from a police helicopter which was in the sky above New York on the day of the 9/11 attacks.

Hovering just 300ft above one of the Twin Towers, the camera peers down on to the burning roof and captures the thick clouds of black smoke billowing out after the planes have gone in.

Never before has anybody outside of official inquiries seen the disaster from such an angle.

The footage makes clear that the top section of both buildings was turned into a charred wreck when they were struck and there was no hope for those trapped inside.

The 17-minute long film was part of the evidence used by the official inquiry into the collapse of the World Trade Centre buildings.

The investigation, conducted by the National Institute of Standards and Technology used the Freedom of Information Act to get hold of the footage but it was not made public.

Now, however, it has been posted online by secret-sharing website Cryptome along with a series of pictures taken by NYPD helicopters that were on duty that day.

The film begins with the helicopter flying past the Twin Towers after both have already been struck by planes.

It hovers to within 300ft of the roof of one so that the acrid smoke billowing out into the sky can be clearly seen.

The flypast also gives a chilling view down the tower showing the extent of the damage and the flames coming out where it was struck by the passenger jet.

The police helicopter then lands in a park nearby and carries on filming, capturing thousands of people running for their lives through the streets.

Throughout there is panicked but but indistinguishable chatter over the airways until the film cuts to the helicopter back in the air.

By that time the South Tower had already collapsed.

‘The whole side! It’s gone, it’s the whole tower. Holy cr**!’ says one of the pilots.
‘They knocked the whole freaking thing down! The other one’s going to go. Holy...holy cr**. The whole tower’s down.’

White and grey smoke clouds burst through the streets and out towards the Hudson river and engulf the whole of downtown Manhattan.

‘Holy God damn, they did it. The second tower fell’ the pilot says.

The helicopter then spends some time hovering in the sky watching the remaining tower pour smoke into the air like a giant chimney before landing at their base where the camerman films the North Tower collapsing.

An unidentified voice on the police radio can be heard saying: ‘The North Tower is down. All personnel be advised the North Tower is down.

‘Request assistance, request...Unit request’.

The police pilot says: ‘Holy s***. That’s it, biggest disaster in the world, right there’.

Also released by Cryptome were dozens of photographs taken by NYPD helicopters which show the collapse of the Twin Towers from angles which have not been seen before.

In one particularly striking picture the South Tower appears to be bend over and collapse in on itself as it crumbles to floor.

Some 2,996 people died during the September 11 attacks in 2001, the worst non-wartime loss of life in U.S. history.

The three-year probe by the NIST blamed fires caused by the planes that flew into the the Twin Towers for causing the ‘extraordinary event’ that led to their collapse.