Watch out for this costly cell phone scam

If your cell phone rings just once, don't simply call back an unfamiliar number. It could be a costly scam.

The Federal Trade Commission and state attorneys general are warning about a nationwide rise in the so-called one-ring cell phone scam. 

It works like this: Scammers auto dial cell phone numbers at random, letting the phones ring just once before hanging up. They hope that would-be victims, being curious or believing the call was cut off, will call back. When they do, they hear a message telling them they've reached an operator and directing them to hold. In some cases the calls go to adult entertainment or other expensive services. While the victims wait, they're hit with expensive per-minute charges.

The calls have three-digit area codes that seem as though they belong to the U.S., although they're actually from other countries, including the Dominican Republic, Jamaica, the British Virgin Islands, and Grenada. The area codes include 268, 284, 473, 664, 649, 767, 809, 829, 849, and 876.

The Washington State attorney general reported that victims were charged $19.95 for an international call and nine dollars a minute.

To avoid being ripped off, don't automatically call back a number you don't recognize. Wait for the person to call back or use a web search to see whether you can get more information about the number, including the location of the area code. Carefully check your phone bill. Look for small amounts: scammers sometimes charge just a few dollars, hoping victims won't notice. Report any unexpected charges to your carrier.

— Anthony Giorgianni