Police in Hackney are issuing an image of a male they wish to speak to following a violent assault in Stamford Hill.
At approximately 20:00hrs on Tuesday, 20 June a number of male youths entered Morrison's supermarket in Stamford Hill, N16.
A security guard working at the shop observed one of the group stealing a bottle of alcohol and apprehended him.
As he held on to the suspect, the male smashed the glass bottle he had stolen over the guard's head. Despite receiving a cut to his head, the security guard continued to detain the male - however the rest of group returned and threatened staff. They freed the male and all of the group ran off.
The victim, aged in his 40s, was taken to hospital for treatment before being discharged.
Anyone with information is asked to call Hackney CID on 020 7275 3632 or contact Crimestoppers anonymously on 0800 555 111.
No arrests; enquiries continue.