The Better Business Bureau warns of a credit card scam in which scammers already have your credit card information, but need the card’s security code (the three-digit number located on the back of your credit card).

Someone calls you claiming to be from your credit card company’s security and fraud department. The caller already has your credit card number by some form of identity theft, may provide a badge number and tells you your card’s been flagged for unusual purchasing activity.

You’re asked if you purchased an item, like an Anti-Telemarketing Device for $497.99. When you say no, the scammer says your account will be credited and explains the charge is by a company being watched for making unauthorized credit card charges ranging from $297 to $497.

After reciting your address for verification, the scammer needs to verify the credit card’s in your possession and asks you to recite the three-digit security number on the back. Armed with your address and credit card’s security code and account number, the scammer has what’s needed to go shopping on you.

The best protection against schemes like this is to always verify the legitimacy of requests for personal information. While you may be asked to confirm your identity, your credit card company won’t ask you to verify information it has on file, disclose security codes or prove the card’s in your possession.

If you think you’re an identity theft victim, close credit card accounts you think may have been tampered with and review statements for unauthorized charges. File a police report and a complaint with the Federal Trade Commission at www.consumer.gov/idtheft or call (877) IDTHEFT.

Also, place a fraud alert on your credit reports by contacting one of the three credit reporting companies:

• Equifax: (877) 576-5734; www.equifax.com

• Experian: (888) 397-3742; www.experian.com

• TransUnion: (800) 680-7290; www.transunion.com.

And, order a free credit report and review it carefully. You can get additional information on identity theft, including a free brochure, from your BBB. Visit www.bbb.org or call (937) 222-5825 or (800) 776-5301.

John North is president and CEO of the Dayton Better Business Bureau.