Video shows the moments after a police helicopter crashed into a crowded pub in Glasgow.

One onlooker filmed the scene as people stood outside The Clutha in Stockwell Street wondering what had caused a huge crash and filled the venue with choking dust.

Customers are seen wandering back into the pub, not realising that a helicopter had spun out of control and smashed into the roof.

Eyewitnesses were watching a live ska band when the ceiling started to cave in.

Grace MacLean told Sky News: "There was a band on, they were quite loud, and we just kinda heard a whoosh and some smoke.

"We looked around and no-one really knew what was going on. Everyone just carried on listening to the band. And then we kind of looked again and the roof was gradually coming down.

"Someone started shouting and the band cut the music ... and then all of a sudden this cloud of dust came.

"You couldn't breathe for inhaling a mouthful of dust. You couldn't see anything. You were clawing at the walls to see where the exit is. No-one had a clue what was going on. There was no loud noise.

"People were helping each other out. Everyone started helping people who were hurt. People had some head injuries. Lots of people were covered in dust. There were lots of people shocked. No-one knew it was a helicopter crash until people told you."

William Byrne, who was watching the band play with his brother, said: "I thought 'has the band blown something', something electrical like a speaker or something, you could never have foreseen that it was something remotely like a helicopter.

“I didn’t know until about 15 minutes later that it was a helicopter. My thoughts were that something just blew and then the ceiling just collapsed. I had no concept of what it may have been that happened."

Labour's international development spokesman Jim Murphy happened to be driving past the pub immediately after the crash.

"I jumped out and tried to help," he said. "There were people with injuries. Bad gashes to the head. Some were unconscious."

He described how a human chain formed to help pass unconscious casualties out of the pub so that "inch by inch, we could get the people out".

Scores of passers-by in the area ran to the venue after seeing or hearing the aircraft go down.

Connor Gillies, from Radio Clyde News, told Sky News of the "scenes of chaos" and "continuous stream of sirens" in the area on Friday evening.

Mr Gillies described seeing "blood on the shirt" of Mr Murphy, who he said was "clearly very shaken, very upset by the whole thing".

Wesley Shearer, who posted pictures on Twitter of the scene, said: "This is unbelievable. Just spent 20 minutes pulling people out of the bar."

Jan Hollands, who also tweeted pictures from the scene, said she heard the crash and described it as "scary".

:: Police have issued an emergency telephone number for concerned relatives - 0800 092 0410.

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