A. The victim of fraud is the one responsible for reporting identity fraud.
First and foremost, you are the only one who knows yourself. Not the police nor any of the three credit reporting agencies. So whenever something happens like purchases made using your credit card and you know for a fact that you did not use your card nor give permission to anyone to use your card, then you are a victim of identity fraud.
You must report to three major credit card bureaus. Call their fraud departments directly and request that a fraud alert be placed on your file. This will alert your creditors to contact you directly before any credit card purchased be made and confirm whether the transaction is legit or not.
You also must close accounts that you believe have been tampered with and file a police report. You must also contact your bank, card issuers, and other creditors personally to inform them of identity fraud at the same time protect you rights.