A man was left with a double fracture to his jaw after an argument about a taxi in Gipsy Lane, Luton.
The 49-year-old was close to the car park of Venue 360 at about 12.20am on September 22, when an argument broke out between his partner and a group of people about a taxi.
As the man went to intervene he was punched in the face by a man wearing a grey suit.
He lost consciousness and fell to the floor.
He was taken to hospital for treatment to his jaw which was fractured in two places and required surgery.
If you saw or heard anything please call Det Con Steve Francis on 01582 394316 or text 07786 200011.