A cyclist taking part in last night's Dunwich Dynamo from London to the Suffolk coast has filmed the moment he and two friends he was riding with crashed when some teens pushed a bike into their path as they rode through Woodford Green.
Richard Frazier wrote on Instagram: "We left London Fields last night as a group of five, but less than 90 minutes later were reduced to four following a ridiculous decision from a group of kids near Epping.
"They rolled an old mountain bike out into the front wheel of @bamesjerry. I was behind him and went over the top and @nicknumbernine didn't have the time to stop either.
"Thankfully James and I got off relatively lightly, but @nicknumbernine ended up on the train back to London far sooner than any of us would've liked."
In a subsequent comment, he said: "No payback beyond giving their bike to a group of chaps a pub opposite.
"A ridiculous thing to have done, but they can't have been more than 14 years old. None of us were ever going to do anything more than go completely mental at all of them."
Another rider, Charlie Thomas, said in a post on the Dunwich Dynamo Facebook page that he had been deliberately knocked off his bike by a motorist in Epping.
He wrote: "Got hit off my bike by a car just before Epping high st. The driver was speeding, overtook us and clipped my shoulder and wiped me out. And didn't stop.
"I continued to the white hart where the amazing staff looked after me. I'm on my way to Princess Alexandra A&E to get my shoulder looked at and arm stitched up. Bikes un-rideable. Helmets cracked. F*cking arsehole."
He said the incident happened between 10.30 and 11pm on Saturday evening and that the vehicle was a navy blue people carrier.
He added that an occupant of another car, a Mercedes A Class, shouted "another one bites the dust" as they drove past.
Founded in 1993 by chance when a group of bike couriers decided to ride towards the moon one summer's evening and found themselves arriving on the Suffolk coast several hours later, the Dunwich Dynamo now attracts huge numbers of cyclists each July.