Gardai are searching for a man who threatened staff in a shop on the Avenue Road with a "large knife" before making away with a sum of money from the till.
The man entered the Avenue Road shop at 9pm on Wednesday, 28th March.
Gardai say the man fled the scene on a bicycle. He was wearing a scarf and hood to cover his face.
Anyone who might have seen the man on Wednesday night is asked to contact Dundalk Gardai at 042 93 88400.