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Some debt collectors can be ruthless, calling all hours of the day and night and threatening arrest and violence if they don't get paid. Speaking in heavily accented English, they may use foul language, and they don't hesitate to lie about who they are, where they are calling from or what they will do to you if you don't pay up right away.

The thing is, these particular callers are not really debt collectors. They're extortionists and scammers, calling Americans from other countries as part of a long-running con to get money from consumers who at some point applied for online payday loans. One firm allegedly raked in $5 million before the Federal Trade Commission stepped in.

We've written numerous articles about how to spot an overseas payday-loan debt-collection scam. But what if you know it's a scam and you just want the calls to stop? A reader posed the following question on our blog recently:

"I have been receiving calls from someone who is saying I owe money to a First American Cash Advance. Well, first of all, I can't even get a payday loan -- I am in the military. Besides that, they [have] been calling my work and it's been difficult. The number appears on my caller id as out-of-area call (911). I'm not sure what that means. They say they work for the FBI and if I don't pay I could go to prison. I never even received anything in the mail about this, as well as never having a payday loan, so I know it's fake. I just want them to stop calling and harassing me. I can't even understand them and they're saying they will have me investigated. What should I do?"

Strategy No. 1: Do not engage. Do not get into a conversation with them in the first place. "Hang up on them," says Mark Fullbright, a senior fraud investigator with Identity Theft 911. "They are effective because people want to converse about the debt and prove they did not owe a payday loan debt. There is nothing to prove to these scammers. Do not provide anything to them."

Attorney William Howard with the Florida-based law firm of Morgan & Morgan warns that "Just like any other volume business they are calling thousands of people and they are looking for the vulnerable and the gullible." If it doesn't sound like they are going to get any money from you, they're more likely to move on to someone else.

Strategy No. 2: Ask for written verification. If you have defaulted on a payday loan and are worried this could be a real attempt to collect a debt, insist the collector put information about the debt in writing. This is your right under the federal Fair Debt Collection Practices Act, and legitimate debt collectors know they must comply, explains Howard. Don't settle for an email confirmation. And don't be intimidated if the caller threatens you, saying that there is no time for that because you'll be arrested today if you don't pay, for example. "You won't be arrested," says Howard.

Strategy No. 3: Turn the tables on them. If the caller tells you that the agency is taking you to court, "ask for the specific case number and court it is allegedly filed in," says Steve Rhode of GetOutofDebt.org. "Call the court to confirm. You won't be able to because it's a scam." You'll know this is a scam before it gets to that point, anyway, because when you are sued you must be served with a written notice of the lawsuit.

If the caller claims to be with a law enforcement agency, ask for specifics: the caller's name and which agency he supposedly works for (for a police officer -- the specific city, county or state, for example). Just as you have the right to ask a police officer who pulls you over in an unmarked car for identification, you have the right to verify anyone who calls you claiming to be with law enforcement.

Let the caller know you will be calling that agency directly to confirm his identity before you talk further with him. Of course, you'll come up empty-handed, as neither the FBI nor police officers are debt collectors. Be sure to tell the caller that if his story doesn't check out, you are reporting the call to that same law enforcement agency. "Tell them you are going to call the cops on them," insists Howard.

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Strategy No. 4: Record and report. Consider recording the telephone call, but make sure youg get the caller's OK if that's required by your state. If you don't record the call, take notes so you can file a complaint.

"All consumers who get these threatening calls should file complaints with the Federal Trade Commission so that they have a record of the claims and the numbers called from," says Jean Ann Fox, the director of financial services at the Consumer Federation of America. "The FTC cannot handle complaints individually but needs a large repository of complaint information to assist in enforcement."

It's also a good idea to send a copy of your complaint to your state attorney general, Better Business Bureau and the Consumer Financial Protection Bureau. Rhode also suggests filing a complaint with the Federal Communications Commission, which lets you report spoofed phone numbers (phone numbers that are fake as in the "911"" call mentioned above). The next time one calls, tell him you have reported him to the consumer protection agencies and that you'll be recording or taking notes of everything he says from now on to include with your complaint.

Eileen commented on our blog, "I stayed calm and just repeated my normal response 'I need to inform you that I was advised by my attorney to inform you this call is being recorded and can be used as evidence.'" She adds, "I agree the best thing you can do, is to stay calm and just repeat the same things over and over, getting upset only proves they can get to you and they will continue to call you hoping you will just pay them."

Strategy No. 5: Hire an attorney. Howard says that once his clients tell the callers that they are represented by an attorney and give the collector his name and number, the calls usually stop. "They may realize that this isn't the easiest mark," he says.

Strategy No. 6: Change your phone number. If other methods to stop them don't work, you may want to consider changing your phone number. Of course, "It is a great inconvenience to have to change your phone number," says Fox.

And, unfortunately, doing so may not stop the scammers, warns Fullbright, who has worked with clients who were still harassed after they changed phone numbers. Plus, Howard warns, "when you change your number there is a chance you will get calls for the person who previously had the number and couldn't pay their bills." You may also be foisting the problem on the next person who gets your phone number. My teenage daughter still fends off collectors trying to reach the person who previously had her cellphone number -- and it's been well over two years since she got that number.

Another alternative is to check whether your phone company offers a call screening service that requires callers to announce themselves before their calls go through. There's likely to be a fee for that service, though. A free alternative is a Google Voice number that lets you manage which calls go straight through to you and which ones must be announced or go straight to voice mail.

Strategy No. 7: Have fun with it. These kinds of calls can be scary and stressful. Nicolette commented on our blog, "I have nightmares and dread when the phone rings. I just wish he would stop calling." But if you've figured out it's a scam, then maybe you can try to make their lives miserable. One of my friends told me that when he gets harassing collection calls, he just starts "messing with the caller," asking them what they're wearing or finding other ways to "creep them out." A commenter on our blog who said he worked briefly for one of these firms suggests, "Ask them if you are American, then tell me a few lines of our national anthem." I've also heard from consumers who put the collectors on hold and don't come back, blow whistles or air horns into the phone or play obnoxious music at full volume. (I am not suggesting these methods for avoiding legitimate collection calls, of course.)

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One of our readers, going by the name 2Creative, shared some "creative" ways to deal with these scammers in his comment on one of our previous stories. He suggests, for example, that you ask if they are related to the deceased (insert your name here as the "deceased") or just a family friend, because "the viewing of the body (is) for family only, but the memorial service is open to everyone." Ask if they would like directions to the funeral.

He says, "I started getting these calls about a year ago. (Using creative tactics) they do stop calling me for about 6 months . . . so the way I figure it, a little time out of my day to give them back a taste of their own medicine is worth it for 6 months of peace and quiet."

Hear more in an interview with attorney William Howard about how these scams work and what to do to protect yourself. It includes a recording of an actual call made by one of these scammers to a consumer. Listen online here, download the podcast here, or listen on iTunes.

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