Police have renewed their warning to business owners in Mid Ulster to be on the look out for counterfeit cash.
In recent days there have been a number of attempts to pass fake notes in shops in towns, including Cookstown and Dungannon.
Police say £20 and £50 notes have been used.
The police are urging counter staff to be vigilant and report anything suspicious to them.
In a Facebook post, Dungannon PSNI said: “You know the checks to carry out on all notes, remind your staff to do them too, ensure your CCTV is recording and contact us if anyone attempts to use them on your premises.”
For additional advice contact your local Neighbourhood Team.