Daredevils have been filmed backflipping from Tower Bridge into the Thames amid the heatwave - prompting a safety warning from London Fire Brigade.
The brigade urged the public not to repeat the social media stunt, which saw four men in swimming gear somersaulting 30 feet into the river.
One of those involved, Adam Szaniawski, posted the footage on Instagram with the caption: “Flipping off Tower Bridge with the boys”.
The 18-year-old told the Sun: “We were all buzzing off each other’s hyped-up energy that it almost felt natural.”
However, he added: “We thought about the dangers and I’m not encouraging people to do this.”
The video shows the daring stunt from different angles, with three of the men attempting the jump before a fourth joins them.
“I hope you fellas didn't swallow any microplastics,” said one social media user in response, while another added: “RIP. Probs like 50 diseases in that river alone”.
However, the London Fire Brigade said on Tuesday: “While this may seem like a good time, diving into water like this leaves you at risk of cold water shock, no matter how fit you are.
“We are calling for people to stick to designated swimming areas and think before diving in”.
There were nine accidental drownings in London last year. The latest warning came after a teenage boy lost his life at Fairlop Waters in Ilford, east London, last week.
