Police are warning of counterfeit notes in circulation after reports from the Newarthill and Carfin areas.
A forged £20 was used to purchase goods from a convenience store on Carfin Road around 5.40pm last Wednesday (January 27).
Officers have released a description of the suspect in the hope of attracting witnesses.
He is described as being white, aged 25-30, 5’6”-5’7”, slim with short dark brown hair, and was wearing a black jacket and trousers.
An hour or so later, a second report was made to police that more counterfeit £20 notes had been passed, this time at the golf club on Hagen Drive.
A police spokesman said: “Even with cleverly forged notes, there is usually a significant difference in comparison to genuine notes.
“If you suspect a note you have been passed is counterfeit, examine the print quality, check for a watermark and see if there is a metallic security thread. Use a detector pen if you have one.
“If you still have suspicions or doubts, keep the notes and contact police.
“It is a criminal offence to hold or pass a note that you know to be a counterfeit.”
Anyone with information is urged to call Police Scotland on 101 or Crimestoppers on 0800 555 111.