The practice of third parties placing unauthorized charges on wireless accounts is called "cramming."
Do not answer, do not call back --
One-Ring Phone Scam on the Rise - BBB News Center: "One-Ring Phone Scam."
Consumers around the country report an increasing number of what is known as the "One-Ring Phone Scam." Perpetrators of this scam program their computers to blast out thousands of calls to random cell phone numbers, ring once, and then disconnect. This scam relies on consumers calling back missed calls, which then connect them to a paid international adult entertainment service, 'chat' line, or other premium service located outside the country. Victims who return the call are billed a $19.95 international call fee, along with per minute charges for the unwanted "premium service," which can be $9 per minute or more. In some cases, the scammers may only put through a small charge of several dollars, so it won't arouse suspicion. . . . (read more at link above)
Better Business Bureau recommends if you don't recognize an out-of-state telephone number on your caller ID, ignore it and if you do answer, do not call back. Also you should check your cell phone bills carefully and inform your carrier if you spot any unauthorized charges. The earlier you document the fraud, the better your chances of having some or all of the charges removed
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