Footage shows a trio of youngsters entering the shop asking to purchase cigarettes and drinks. On being refused, a suspect launches an attack on the salesman with a knife whilst another smashes a bottle over a second victim's head.
Officers from Westminster attended to find a 44-year-old man suffering a stab wound to the left side of his face, and 21-year-old man with a cut also to his face.
Metropolitan Police say they were called at around 2.15pm to reports of people fighting in Station Food & Wine in Edgware Road, Paddington on July 7.
Both injured men were provided first aid by the first officers at the scene, until paramedics arrived.
The two men were taken by London Ambulance Service to hospital for treatment.
Detectives from Westminster Borough CID investigating the serious assaults are appealing for help in identifying three people they wish to speak to in connection with the incident.
Suspect 1 [ref: 218168] is described as being of average build with short black hair.
Suspect 2 [ref: 218169] is described as slim build with short black hair.
Both suspects were wearing a grey hooded top, black trousers and black shoes.
Suspect 3 [ref: 218170] is described as being of slim build and was wearing a black top.
PC Richard Kidd from Westminster CID said: "Both of the victims in this attack are very fortunate not to have suffered a fatal injury as a result of this attack."
Anyone with information should contact officers via 101 or Crimestoppers anonymously on 0800 555 111.
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