The UK's freerunning community has been left "scarred" after the death of Nye Newman.
The 17-year-old's parkour group, Brewman, says he died on New Year's Day in an accident on the Paris Metro.
The group has denied he was train surfing at the time.
Speaking to Newsbeat, his friend Jacob Kohn described Nye Newman as "such a great person, an independent person - he was always doing stuff for everyone else".
"It's going to leave a big scar on the freerunning community.
"I don't think anyone's going to get over it anytime soon. It's going to be tough."
Brewman posted a video of Nye freerunning in Paris days before he died.
Jacob says he knew Nye when they first started freerunning together, but says he's not doing it any more.
"When I found out what happened I was inconsolable," he says.
"He knew everyone and everyone he knew saw him as their best friend. It's heartbreaking.
"Nye was probably the most positive and the most outgoing person I've met in my life.
"He was always jumping around - he had probably the biggest flip gap of anyone I know. He could flip further than anyone I know.
"He would make it look so easy because he had such a big jump - he would always pull off the sketchiest things.
"He loved to travel. He was always going all over the world.
"He left an imprint on pretty much everyone he ever met."
A statement posted on Brewman's Facebook page paid tribute to him.
"Nye was an incredible human being who was always up for anything, he experienced things in his short life, that many won't experience in their life times.
"He was always up for anything, and he always gave a positive outlook to any situation.
"He inspired so many people through his enthusiastic lifestyle and the assisted creation of Brewman.
"He was the type of guy who had no regrets in his life and lived every day like it was his last."
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