Thames Valley Police are appealing for witnesses after around 15 men were seen fighting in Amersham.
Between 11.15pm and 11.45pm on Sunday, March 26, a group of around 10 to 15 men were seen to be fighting in a layby on Station Approach, opposite the train station.
One of the men got into a blue car and drove at another of the men, who sustained a serious leg injury.
The man, in his twenties, was taken to hospital, where he remains.
The blue car is described as a saloon shape with four doors.
A 42-year-old man, a 45-year-old man and a 22 year-old man, all from Chesham, have been arrested on suspicion of committing grievous bodily harm and remain in police custody at this time.
Investigating officer PC Melissa Todd, based at Amersham Police Station, said: “We are appealing for anyone who may have witnessed this incident to please come forward.
“We’d also ask any motorists who were in the local area and who may have dashcams to check any footage in case it has captured something that could assist our investigation.
“Anyone with information can call 101 or make a report online, quoting reference 43230134381.
“Alternatively, if you wish to remain anonymous, you can contact the independent charity Crimestoppers on 0800 555 111 or via its website.”