A £25,000 reward has been offered for information leading to the conviction of an armed robber who raided a post office in Hove.
A woman worker was threatened with a gun in the latest raid at Melville Road Post Office on 3 December.
It was the third robbery at the premises since 23 September and detectives believe the same man may be responsible.
Sussex Police have issued an efit of the suspect.
In the latest raid, the robber, who was wearing a balaclava, made off in a black Ford Mondeo with a white bonnet, registration P170 KVP.
The car was abandoned in Norfolk Road, Brighton and the man ran off along Western Road.
Police said the man purchased the vehicle before the robbery from legitimate owners who came from outside the Brighton area.
A force spokesman said the car may have been parked up or hidden away for at least a week prior to the robbery.
The post office was also targeted on 23 September and 4 October. The reward money is being offered by the Post Office.
CCTV images of the raid and a picture of the car have also been released in an appeal for information.