A 21-year-old man died after the car he was travelling in left the road and collided with a tree.
Thames Valley Police is appealing for information after the fatal incident in Aston Abbotts, Bucks.
At around 5.30am on Sunday (August 29), a black Mercedes ML55 was travelling on the Cublington Road towards Cublington when it came of the road.
Police attended along with South Central Ambulance Service and Buckinghamshire Fire and Rescue Service.
The 21-year-old man who was in the car died at the scene.
Two other occupants of the vehicle, two men aged 23, sustained injuries and were taken to Stoke Mandeville Hospital where they are currently being treated.
The road was closed while officers investigated the circumstances of the collision and it was reopened by 10.20am.
Police would like to speak to anyone who saw the collision or saw the vehicle prior to the collision or has any information about the incident.
Contact investigating Officer PC Alan Turnbull from the Serious Collision Investigation Unit in Bicester via the 24hr enquiry centre on 101 quoting URN 271 29/8.
Alternatively call independent charity Crimestoppers, anonymously, on 0800 555 111.
> Two 23-year-old men from Aylesbury have been arrested on suspicion of causing death by dangerous driving.