This video shows the moment youngsters scaled two of the country's most famous rollercoasters after hours.
The group of parkour enthusiasts climbed Stealth as well as the looping ride Colossus at the Chertsey theme park on Easter Sunday evening (April 16).
The teenage co-founder of parkour group Brewman, Rikke Brewer, uploaded the shocking footage to Youtube, entitled "Sneaking into Thorpe Park! (Caught) climbing Stealth!"
The video shows 18-year-old Rikke planning to climb Stealth and then arriving at the theme park with three friends, who all jump over the fence onto the premises.
They then head straight for Stealth and begin climbing the UK's second highest rollercoaster.
Later, they ascend Colossus before the video shows them being reprimanded by security guards with a fire engine in the background.
At the end of the video, Rikke said: "We have just been detained and banned for two years at Thorpe Park. Pretty jokes."
He posted a photo of the letter banning him on social media, saying he used a fake name so he could return to Thorpe Park soon.
The letter said: "In accordance with the Thorpe Park Regulations, your actions today have constituted a breach of our terms and conditions.
"This has resulted in our refusal to allow your to enter, or remain, on Thorpe Park property."
It continued: "As a result of your actions, you are now banned from entering Thorpe Park property, for a period of 24 months.
"Failure to comply with the ban may result in police action, or an action in Civil Recovery to recover any losses caused as a result of your actions in gaining unauthorised access to our premises."
Brewman denied any involvement.
They said: "The climbing of Stealth and Colossus were nothing to do with Brewman parkour as a team so we will not be making a comment."
A Surrey Fire and Rescue Service crew attended Thorpe Park at around 10.15pm on Sunday to ensure the parkour enthusiasts descended safely.
A spokesman for Merlin Entertainments, owner of Thorpe Park, said: "Thorpe Park takes trespass extremely seriously."
He added: "It has a zero tolerance policy towards this behaviour which is irresponsible, foolish and potentially very dangerous for those individuals as well as others. As such, we will be pursuing legal action against those involved.
"We can confirm that last night [Sunday] four youths broke in and attempted to climb one of the rides.
"They were spotted very quickly by our security team and the police were informed.
"One of the young men had difficulty descending from his position and Surrey Fire [And Rescue] Service were called to help him down safely."
A spokesman for Surrey Fire and Rescue Service said: "A group of youths broke in and climbed to the top of the Stealth ride.
"By the time we got there, they had rescued themselves. The youths broke in nearly five hours after the theme park had closed.
"I think they saw the better of it and climbed down as it is crazy going that high."
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