Shopkeepers in Leigh are being visited by Leigh PCSOs after counterfeit notes were seized by officers.
Police have received five reports about the bogus notes being handed over at shops in Leigh.
PCSO Carol Fox, of Leigh police, said: “The fake £20 notes have been used at convenience stores along the A13 corridor in Leigh over recent weeks. "In response, I have been visiting local shops to offer advice to staff about checking the validity of paper money.”
Anyone with information about the production or use of counterfeit currency is urged to contact their local police station on 101 or Crimestoppers, in confidence, on 0800 555111.