It happened on the B3081 near Verwood - he had to be cut free by firefighters.
New Forest: 13-Year-Old's Ankle Broken By Road Rage Driver
Police in the New Forest are looking for a driver who broke a 13-year-old boy's ankle as he was filming his friend skateboarding.
His friend was recording him riding along Bolderwood Road on Saturday, when a man driving a dark-coloured Vauxhall car appeared to try and run the boy off the road.
The boy then shouted and the man stopped his car and approached him. He grabbed the boy before pushing him to the ground and standing on his ankle and foot.
The man then also made the boy delete the footage from his camera before leaving the scene in his car.
It happened between 11.30am and 12.30pm.
The man is described as white, aged about 40, about 6ft 5ins tall and of a large build. He had a long ginger beard and was wearing a hat, jeans and a jacket.
PC Jason Andrews said: "This was a cowardly assault on a defenceless young boy which has resulted in the victim sustained a broken ankle and chipped on on his foot.
"The weather was good this day and so the area was likely to have been busy with cyclists, dog walkers and tourists and I would urge anyone with any information or who witnessed the incident to contact me."
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