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://www.ndtv.com/article/india/ex-call-cen ... 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:
I just received a very spooky call from this number. I did not answer, they left a voice message. It started off as a whispering like a practice of what he was going to say, then the man with a deep Middle Eastern (Indian) Accent said he was calling from the Department of the IRS regarding a "case" against me and if I didn't call back in the next few hours I would be the sole proprietor to legal action being taken against me. I knew it had to of been a scam, it's easy enough to spoof numbers to come up on Caller ID noting "Washington DC", anyone can do it nowadays.. it is totally illegal and I hope whomever is behind making these calls gets caught. They could at least learn to speak English better, or hire someone that speaks English with no accent to try and scam people, I highly doubt the IRS or any Government bureau or department has Middle Easterners making threats to people over the phone about "cases" which he left no further information about.