People and businesses are being urged to be vigilant for counterfeit €50 notes.
Gardai believe there is a sizeable quantity of the forged money currently in circulation around the country.
It comes after a recent raid on a premises on the North Circular Road in Dublin.
Printing paper to produce two million euro worth of counterfeit fifty euro notes was discovered at the scene.
A large scale printing press was also seized.
Three men arrested during the operation appeared in court earlier this week.
Superintendent David Taylor, from the Garda Press Office, says people should contact Gardai if they have suspect notes:
