A 21-year-old has been arrested and bailed after reports that a car being driven erratically caused cuts and grazes to a man in his 20s after a collision.
The green Seat Leon then drove away from the car park of Bovingdon Market, where it happened at around 1.10pm on Saturday.
Det Con Anthony Hooper said: “I would appeal to anyone who was in the car park at the time and saw what happened to contact me.
“I would also like to hear from anyone who believes they saw the vehicle being driven in the area that afternoon.”
Anyone with information is asked to contact Mr Hooper via the Hertfordshire Constabulary non-emergency number 101, quoting crime reference D1/14/6180.
Alternatively call Crimestoppers, the independent charity, anonymously on 0800 555 111.
The 21-year-old man from St Albans has now been released on bail until Wednesday, November 12.