A cab driver was robbed by two passengers after he stopped to let them out in the Overstone Lodge area of Northampton.
The 59-year-old private hire driver was forced to hand over cash after he was threatened by two men who he had dropped off at the junction of Shadowfax Drive and Talan Rise in Northampton.
The first robber is described as white, of medium build, about 20-years-old, 5ft 8ins and was wearing a white or cream tracksuit.
The second man was also white, of larger build and about 20-years-old.
The victim was not injured in the incident, which happened on Friday March 1.
Officers would like to speak to anyone who may have witnessed this incident or who may have any information regarding it.
Anyone with information can call Northamptonshire Police on 101 - alternatively, information can be given anonymously to Crimestoppers on 0800 555 111.