The driver of a silver Passat is thought to have been involved in a hit-and-run on the A507 near Shefford.
According to police in Bedfordshire, a man believed to be in his 20s was also involved in the crash which was reported at around 5pm on Friday, September 2.
The incident took place at the A507 roundabout with Chapel Road (Meppershall), A600 Hitchin Road and The Airman Hotel.
The silver Volkswagen Passat did not stop at the scene, and police are concerned for the welfare of the second person - thought to be in his 20s - who left the scene before emergency services arrived.
Police Constable Lisa Wilson, from Bedfordshire Police’s Crime Investigation Team, said: "This is an extremely concerning incident that has occurred at a time when roads were likely to be busy.
"In the first instance, we are appealing to the man the car collided with to come forward.
"We are greatly concerned for his welfare, and it is paramount that he makes contact with us, so we can establish whether he needs medical attention.
"We are also keen to speak to anyone who may have witnessed the collision or saw the silver Passat leaving the scene.
"It will likely have sustained some damage to the front of the vehicle.
"If you have dashcam footage from the area around the time of the incident, or have any further information to support our investigation, we’d like to hear from you.
"If you have dashcam footage from the area around the time of the incident, or have any further information to support our investigation, we’d like to hear from you.
"Anyone with information can report via the online reporting centre at https://www.beds.police.uk/, quoting reference 306 of 2 September.
"Alternatively, you can call independent charity CrimeStoppers, anonymously, on 0800 555 111."
The man who was injured in the crash is thought to have left the area in a white Ford van.
The silver Passat vehicle occupants were described as being white males in their 20s. Both are thought to be clean shaven and one with blonde hair.
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