The armed robber who stole £20,000 from a Hove supermarket is pictured in newly released CCTV images.
And the Co-op has put up a £5,000 reward for the arrest and conviction of the attacker.
He threatened the manager of the Co-op in Church Road, Hove, as he arrived for work and forced him into the shop’s office.
The robber told the manager to open the shop’s two safes but they were controlled by a timer and wouldn’t open until 45 minutes later.
So he tied the manager to a chair in the office and beat him violently.
He then sat opposite him cutting paper and toilet roll with a large knife until the safe opened.
The attacker escaped with £20,000, leaving the manager to be found when one of his colleagues arrived for work.
Detective Constable Robin Aspin, of Sussex Police, said: “The victim was threatened throughout the ordeal and is still extremely traumatised by what happened.
“During the attack he was beaten and was left with painful injuries from being tightly tied to the chair.
“The Co-op is now offering a £5,000 reward for the arrest and conviction of the attacker.
“It is believed he may have been employed previously by the supermarket chain, as he knew a great deal about the workings of the shop.
“Both the bag and knife used by the attacker are distinctive.
“The bag is a limited edition reusable shopping bag featuring a carrot design and was available only in Morrisons stores.
“The larger knife used features a shadow logo of a bull and was only supplied to a number of supermarket chains for use by staff.
“They are not available to the general public.”
The offender is described as white, 6ft tall and overweight, with brown eyebrows and brown eyes and a northern accent.
He was wearing grey frayed jeans, a black top and glasses with no lenses in.
He left by a fire exit at the store although it is not known in which direction.
The robbery took place on Friday 24 September and is the subject of a Crimewatch appeal which can be seen by clicking on this link http://bbc.in/gnlA3j.
Anyone who has any information is asked to contact 0845 6070999 or the independent charity Crimestoppers anonymously on 0800 555111.