Police are warning merchants and the public that counterfeit $50 and $100 Canadian bills are being circulated in London.

They say there has been a recent increase in counterfeit bills that mimic those in the Scenes of Canada series of notes from 1969 to 1979.

Investigators say the bills are not polymer and are primarily $100 banknotes.

Bills from the Scenes of Canada series are valid, but are currently out of circulation, and police say retailers should be highly suspicious of anyone trying to spend those banknotes.