An armed thug attempted to rob a Paisley store with a large knife on Friday afternoon.
The man entered the store on Gallowhill Road around 4.20pm and demanded money from the till.
His face was fully covered by a motorcycle helmet.
A staff member was left “frightened” by the attempted hold-up but nobody was injured.
But the man left without taking any of the items and was chased down the road by a member of the public.
He is believed to have made off in the direction of Montgomery Road.
Officers are appealing for information from anyone who may have seen the would-be thief.
He is described as being white and at the time of the incident, he was wearing a grey hooded jumper, light grey trousers and a black motorcycle helmet.
Detective Constable Stephen Knox of Paisley CID said: “Nobody was injured but this was a frightening experience for the member of staff involved.
“Extensive enquiries are ongoing to identify the man responsible, including reviewing CCTV from both the shop and area. However, we are very keen to trace the movements of the man once he left the store
“I would encourage anyone who believes they may have information which could help identify the man or who was in the area at the time of the attempted robbery to contact police as soon as they can.”
Anyone with information can call 101 quoting incident 2650 of 17 July, or call Crimstoppers anonymously on 0800 555 111.