It's a way to hide your number and even your voice so the person you call doesn't know it's you.
It's a frightening problem.
"I have been receiving very disturbing test messages from an unknown numbers with a New York area code, pornographic pictures, soliciting for services, voicemails now being left," said Jessica Anderson, phone spoofing victim.
Jessica Anderson of Richmond, Virginia knows no one in New York but someone got her number.
"And it started to be more detailed, more disturbing," Anderson said.
We know that voice. It's a spoof voice.
"Hi this is Mr. Bernard, is Sarah Wallace there?" an Eyewitness News intern demonstrated.
The Eyewitness News Investigative intern showed how easy it is to mask your voice through a number of websites that also allow you to hide your phone number.
"We have 1, 2, 3, 4, 5, from Google search I did," the intern said, "You type in your phone number, then the phone number you want to call, and the number you want it to show up as. You could also change your voice?" Then you call a number and it's going to connect directly to your phone."
The websites say you can "prank" people, but what happens when it's not all in fun?
"I just let the phone number go to the voice mail, and the voice was disturbing, asking me for sexual favors, prices," said Jessica.
Jessica says she tried phoning the numbers but only one person called back. That person is WABC photographer Gregory Cintron.
"I called the number back and there's this woman that's very upset and distraught on the phone," Cintron said, "I figured I'd call it and when I call it, a woman gets on the phone, very irate and upset and threatening to call the police on me, that I have been harassing her, and you know. I said, 'I didn't make any calls to anybody.' She said, 'You are calling my number, you're sending me these disturbing things, you're saying this and that,' and I'm like 'Ma'am, I never called your number In the first place.'"
"He kept repeating , 'No, you called me first,'" Jessica said.
"I'm upset and I'm worried because someone's using my number. On the other hand, you have someone that was hurt by it that receiving disturbing messages or images or whatever it is," Cintron said.
So you're probably asking, why isn't there a law against this?
New York Congressman Eliot Engle co-sponsored a bill a couple of years ago to restrict phone spoofing, but it was limited.
Law enforcement and battered women's groups argued the practice is sometimes necessary for security reasons.
"So we said, ok, if it's malicious intent, you could be prosecuted," Engle said, "There are still some loopholes allowing some bad people to do some bad things."
"It's not fair that anyone can call us and disguise their number but know our number and can harass us. That's not right, that's morally not right," Anderson said.
Congressman Engle now plans to call for new hearings on spoofing.
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