The use of counterfeit money was reported at two retail stores in Penetanguishene and Midland on Saturday, Southern Georgian Bay OPP say.
The fake money is described as being $100 Canadian bills, which the suspects used to make in-store purchases, officers said.
Investigators are advising area retailers to beware of the recent incidents and to check and report suspected counterfeit money, police say.
Anyone with information can contact the OPP at 1-888-310-1122 or Crime Stoppers anonymously at 1-800-222-8477.
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