Police are investigating an alleged assault at Stirling Retail Park yesterday afternoon.
An incident occurred at around 4.30pm yesterday following an argument between two men.
One man was punched and fell to the floor close to the cash point at Morrisons, before the offender ran from the scene.
The injured man, aged 33 and from Borehamwood, fell unconscious and was taken to hospital.
A 25-year-old man from Borehamwood has been arrested on suspicion of causing grievous bodily harm and has been released on police bail while investigations continue.