YOUNG people are risking paralysis and even death over a popular seaside trend.
As Brits enjoy the summer sunshine, many are flooding to beaches and lakes to help cool off.
But experts have warned those wanting to plunge into the water must be careful.
Most recently, teens have been spotted hanging off Brighton Palace Pier "like monkeys" before launching themselves into the choppy waters.
Despite there being signs saying, "It is forbidden and dangerous to jump, dive, or swim from the pier", Palace Pier boss Anne Ackord said it's been happening since it opened in 1899.
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She said: "Generations of youngsters fail to appreciate the considerable danger of doing this.
"Unless some formal action can be taken against them, all we can do is try to prevent and advise.
"Our security team spend huge amounts of time trying to prevent these actions each year.
"The danger is greatest at low tide as the jumpers fail to realise how shallow the water actually is."
It comes after a local fisherman spotted a group of teens dangling from the railings this week.
Richard Murrell, 52, said: "They were climbing under the pier and hanging around like monkeys.
"The lifeguards were going over to them in their boat and trying to get them down but they still jumped off.
"It was really shallow at the time and I said they were going to seriously hurt themselves. It was frightening to watch.
"Just swimming underneath the pier can be dangerous enough, but jumping could break their neck and back or worse.
"They might think it is funny but it won't be when one of them seriously gets hurt.
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"It only takes one freak accident to paralyse them or even kill them."
STAY SAFE
Brighton and Hove City Council councillor Leslie Pumm also asked youngsters to reconsider jumping from the pier.
He said: "It might seem like fun jumping from the beach groynes or from the pier but it is actually really dangerous.
"We want children and teenagers to know that in the past, people have been very seriously injured doing this - some permanently.
"You can never be sure how deep the water is or if there are objects in the sea below. And there are currents in the sea around the groynes and the pier that can be very dangerous.
"Don’t jump – you could be putting your life in danger or encouraging others who may not be good swimmers and don’t understand the risks involved."
He also asked parents to discuss the matter with their kids - reminding them there are other places to swim safely.
Plymouth has also had issues with tomb-stoning - with a squad recently patrolling the popular tourist spot.
Councillor Sally Haydon, Cabinet member for customer focus and community safety, said: “We want to keep our young people safe but at the same time ensure there are activities that they can enjoy, as well as tackling anti-social behaviour.
“Tombstoning can be very dangerous and risks include death or life-changing injuries, submerged objects such as rocks which may not be visible, and the shock of cold water can make it difficult to swim. It may also be difficult to get out of the water, and strong currents can rapidly sweep people away.”
