Four people have been injured after a fairground ride came loose this afternoon on Brighton Palace Pier.
A teenage boy is among the casualties and was seen being taken off in a stretcher "wincing".
Emergency services, including firefighters, rushed to the scene just after 3pm following reports the Air Race ride had "failed" and a "piece of a ride had come loose".
An ambulance service spokesman confirmed a male teen had suffered a leg injury and others were shaken but uninjured.
Roger Thorne, 73, and his wife Anne, 78, were among the shocked passersby to see the aftermath of the dramatic incident involving the ride which whizzes upside down and does loops.
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Roger said: "We saw kids on the ride just half an hour before it happened.
"It flips upside down with a lot of momentum.
"When we were walking back to the pier we saw paramedics with a stretcher running up the pier."
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Anne added: "Another paramedic was on a quad bike.
"She grabbed a bag and ran over to behind the railings."
A spokesman for Sussex Police said: "Police and other emergency services are attending Brighton Palace Pier after a fairground ride was reported to have failed at about 3pm on Monday.
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"Initial indications are that four people have sustained injuries that are not thought to be serious at this time.
"There are currently no further details."
The ride is described as taking riders "on an amazing journey which replicates the experiences and sensations of an acrobatic aeroplane flight, banks, loops, dives and weightlessness that will test even the most experienced of thrillseekers".
Anne Ackord, chief executive officer of The Brighton Pier Group, said nothing like this had ever happened before.
She told The Argus: "This is very rare for something to be unexplained.
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"The operator did the right thing by pressing the emergency button as part of our well rehearsed crisis plan.
"We have spoken with the manufacturer who will be flying in from Italy for an investigation."
A passerby added: "A boy who looked in his mid-teens was being taken off the pier on a stretcher.
"He was wincing and the ambulance crews with him gave him a pump to take breaths from."
We'll be bringing you the very latest updates, pictures and video on this breaking news story.
