One of the fake notes seized by the PSNI.
Police are advising local businesses and shoppers to be on the lookout for fake bank notes.
The PSNI said they had received reports of counterfeit £50 and £20 Clydesdale bank notes being used recently in shops in Castlederg.
A police spokesperson said: "We have had reports of these being used in the town over the past week. The same serial number features on all notes – 800746.
"Businesses within the area should remain vigilant. If you have any information about these fake notes, please contact police on 101 quoting 370 of 21/09/2020."
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