Police are continuing to investigate the circumstances leading up to why a man was found unconscious with a serious head injury in the pedestrianised area outside Ryman, the stationery shop, High Street, Sutton, on Monday, 14 November.
The man had been found by a member of the public shortly after 00:30hrs.
London Ambulance Service took the injured man to a South London hospital where he is described as being in a stable condition.
The man, aged between 25-30, remains unidentified. Police believe he may have been assaulted but are continuing to keep an open mind.
If anyone has any information to help police with their investigation, contact Sutton Police Station on 101. Alternatively, call Crimestoppers anonymously on 0800 555 111.