Police Scotland is advising businesses across the Kingdom to be extra vigilant following the discovery of counterfeit notes.
A number of fake £50 Bank of England notes have been presented at retail and licensed premises in West Fife.
Local officers are carrying out various lines of inquiry in an effort to trace whoever is responsible and are today appealing for the assistance of the public.
Community Sergeant Gordon Hood, who is based at Dalgety Bay Police Station, said: “We advise local businesses to ensure staff check all notes when taking payment.
“It is worthwhile for commercial premises to invest in detector lights or pens if not already done so. These relatively inexpensive products can quickly determine whether or not a note is genuine.
“Also, it is a common approach taken by criminals, to pay for a small value items with a high denomination note and as such I urge businesses to be aware of this.”
Anyone who comes across a suspect note is advised in the first instance to report the matter to police on 101 or anonymously through the charity Crimestoppers on 0800 555 111.