Detectives investigating the murder of a shop manager stabbed to death in a suspected robbery have released CCTV footage of three suspects.

Jamie Simpson, 33, was knifed in the neck as he was cashing up at the Matalan store in the Kingsland Shopping Centre in Hackney, East London, on Saturday evening.

Police believe that three men lay in wait inside the shop, and then attacked Mr Simpson in the cash office as he counted the day’s takings shortly before 8pm.

The trio are then thought to have made off via the shopping centre’s rear car park on Dalston Lane.

Mr Simpson, from Herne Hill, South London, who had been assistant manager at the shop for the past three years, was found at about 8.30pm by other staff, who called emergency services.

He was later pronounced dead at hospital. A post-mortem examination revealed that he had died from a stab wound to the neck.

Police searching for three suspects have released CCTV images of the men, their faces partially obscured by hoods.

Detective Inspector Laurence Smith, of the Metropolitan Police, said: “Mr Simpson was completing his day’s work when he was fatally assaulted during a suspected robbery at his store.

“We are appealing for anyone who may have seen anyone acting suspiciously in the shopping centre around closing time or witnessed the assailants making off from the store via the rear car park.

“Mr Simpson was known as a reliable, hardworking and diligent member of staff who would always be available to assist his colleagues and customers.

“We believe that the three individuals involved lay in wait at the store and then confronted the assistant manager. The description that we have of them is of three young black males.”

Mr Smith said the attack was not witnessed by any other member of staff.

He said he believed the attack was intended to be a robbery but he did not know what, if anything, was stolen. It is thought that the Matalan store was specifically targeted, and extra police officers have been sent to the area to reassure the local community.

Billy Clegg, a spokesman for Matalan, said: “The circumstances of the attack are being investigated by the police.

“Our first priority at this time is the welfare of the other members of staff at the store. Our thoughts and condolences are with the family and friends.”

The company announced today that it was offering a reward of up £40,000 for significant information leading to the arrest and prosecution of those responsible for Mr Simpson's death.

Alistair McGeorge, its chief executive, said: “Jamie was a very talented and highly rated sales manager with a great future ahead of him at Matalan. He will be greatly missed within the business. Matalan is doing all it can to help the police investigation and to ensure justice is secured for Jamie and his family.”

Police asked witnesses or anyone with information to call the incident room on 0208 345 1585 or Crimestoppers anonymously 0800 555 111.

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