Guernsey Police warn that a number of counterfeit local £10 notes are in circulation.
Police say the notes look like the real Guernsey £10 but don't have the telltale vertical metal strip woven through them.
They all have the same serial number, F068787.
A number of islanders have handed the counterfeit notes in to Guernsey Police over the past week.
Police Constable Peter Geddes is heading up the investigation and he can be contacted on 01481 222222.
Alternatively, anyone with information can contact Crimestoppers anonymously on 0800 555111.

Guernsey Museums close for the season
First visit of an EU ambassador to Guernsey
Hotel guests help grow a greener Guernsey
Guernsey man seeks donations after 2,000-mile challenge
Charity funds upgrades at Guernsey swimming pool
Under used Guernsey post boxes to close in early November
Capsized trimaran returning to France after Guernsey operation
Guernsey extends French ID card scheme into 2026