Police send out warning after credit card fraud call SHARE ON: Mounties in Bonnyville are warning the public about a recent fraud case in town last week. Police are saying on January 12th they were notified that a person was called by someone claiming to be from Walmart Mastercard and that their account had been compromised. The victim did give out some personal information to the caller but felt uncomfortable and later called the number on the back of the credit card in question. The company informed her that they had no record of the call or issues with her card.