This is a Pakistan or India based IRS scam. Do not fall for it. The IRS does not initiate any legal action via phone.  
Read http://www.treasury.gov/tigta/press/press_tigta-2014-03.htm

As general background information, here are a few things you can do:

1) Report it to TIGTA under http://www.treasury.gov/tigta/contact_report_scam.shtml especially if you have become a victim (lost money, gave personal information etc.). You can also file a complaint with the Federal Trade Commission at ftc.gov/complaint (include “IRS Telephone Scam" in your complaint). This way you can also help the government establish specific fraud patterns.

2) Help kill their phone lines but not by calling them back directly (the number may be spoofed and repeat calls by you may - under exceptional circumstances - amount to harassment). The scammers use Voice over IP lines (e.g. magicJack (Ymax corporation)) to make it seem as if they are calling from the US. This is always against these companys' terms of service and can lead to immediate termination of their contract and blocking of their IP addresses for future attempts to register. Do a reverse look up of their telephone number (e.g. www.whitepages.com) to identify the Voice over IP provider and report it to the company and/or law enforcement (local police and/or state attorney general)

3) If you are really annoyed: call or write to your representative in Congress. As these scams happen all over the country maybe this will trigger a reaction and provide US law enforcement agencies with the political backing and the resources they need to work in India and Pakistan together with local authorities (it can happen, read: http://m.ndtv.com/article/india/ex-call-centr ... mmission-320427). A US task force has already been set up in Jamaica to nab scammers there (see http://www.ice.gov/doclib/news/library/reports/cornerstone/cornerstone7-1.pdf). You can use the following template for your letter (more powerful!) or email:

http://800notes.com/forum/ta-a9526ebadc65cf9/ ... 558497927242748

Harassment

This number belongs to a police scam. The caller claims to be a deputy sheriff, that you missed jury duty and have been given a fine, and if you don't pay you'll be arrested, then he asks for a credit card or debit card number. Under no circumstances would a police officer (legally) ask you for your credit card (debit card or bank account) numbers over the phone. If you have trouble with the law, you will be notified in person or be served court papers.

Yea they called me saying he was from the fraud in larceny unit in he had documents that they needed to serve me so i said from who he says oh its sealed i cant disclose that info so i said give me the number to the place in i call to see what it is so when u call the 2022417879 its says fraud unit whats the case number i reported them to the ftc now bout to report them to the state attorney general office as well

Here are a few warning signs that could signal a debt collection scam:

The debt collector threatens you. Legitimate debt collectors probably won't claim that they'll have you arrested or claim that they or their employees are law enforcement officers.
The debt collector refuses to give you information about your debt or is trying to collect a debt you do not recognize. You have certain rights to ask a debt collector to verify the debt. You can use this sample letter to request this information. Ask for an explanation in writing before you pay.
The debt collector refuses to give you a mailing address or phone number.
The debt collector asks you for sensitive personal financial information. You should never provide anyone with your personal financial information unless you are sure they're legitimate.

If you think that a caller may be a fake debt collector:

Ask the caller for his or her name, company, street address, telephone number, and professional license number. Many states require debt collectors to be licensed. Check the information the caller provides you with your state officials, or the state in which the debt collector holds a license. If the caller refuses or is unable to provide you with information about his company, or if you can’t verify the information he provides, do not give money to the caller or company.
Tell the caller that you refuse to discuss any debt until you get a written "validation notice." This notice must include:
The amount of the debt
The name of the creditor you owe
A description of certain rights under the federal Fair Debt Collection Practices Act
If a caller refuses to give you all of this information, consider requesting this information in writing or seeking assistance before paying the debt to make sure the debt, and the company, are valid.

Tip: You can consider sending the collector a letter requesting the information by using one of the CFPB's sample letters. You can also submit a complaint to the CFPB or you can contact your state Attorney General’s office.

Do not give the caller personal financial or other sensitive information. Never give out or confirm personal financial or other sensitive information like your bank account, credit card, or Social Security number unless you know the company or person you are talking with is a real debt collector. Scam artists, like fake debt collectors, can use your information to commit identity theft such as:
Charging your existing credit cards
Opening new credit card or checking accounts
Writing fraudulent checks
Taking out loans in your name
Contact your creditor. If the debt is legitimate – but you think the collector may not be – contact your creditor about the calls. Share the information you have about the suspicious calls and find out who, if anyone, the creditor has authorized to collect the debt.
Report the call. Submit a complaint with the CFPB or get in touch with your state Attorney General's office with information about suspicious callers.
Stop speaking with the caller.If nothing else works and you believe the calls are fraudulent, send a letter demanding that the caller stop contacting you, and keep a copy for your files.
Tip: You can use this sample letter to write a letter demanding the debt collector stop contacting you. By law, real debt collectors must stop calling you if you ask them to in writing.

Tip: If you're having trouble with debt collection, you can submit a complaint with the CFPB online or by calling (855) 411-CFPB (2372).

http://www.consumerfinance.gov/askcfpb/1699/h ... legitimate.html