Officers are appealing for information following an incident in Dunstable Road, Luton on Saturday (20 January).
Around 9.30pm, police were called to reports of an affray between a number of people and involving suspected weapons.
It is believed the affray broke out following an altercation between the drivers of two vehicles that then sped off, leading to a collision involving one of the vehicles and a separate vehicle.
Emergency services attended and one person sustained serious injuries.
Detective Sergeant Janet Wilkins from Bedfordshire Police’s Criminal Investigation Department said: “We are working to establish the circumstances around this incident and are appealing to the public for help.
“We’re encouraging anyone who was in the area at the time to provide information or dashcam footage that could support our investigation.
“We also believe a silver vehicle was present at the time of the collision and are asking the occupants/owner to come forward and contact us.”
Anyone with information is asked to report online or call police on 101, quoting reference 406 of 20 January.