In Peterborough, two men who pulled off a robbery at a jewellery store, and police believe they may have pulled off the same scan elsewhere, including Barrie.
They filled out a credit card application using information stolen from a Toronto man.
Then they bought a diamond worth about 13-thousand dollars.
The victim found out about the scam when the bill arrived.
Stores in Barrie, Kingston and Guelph may have also been hit.