who is it? is this a scam?

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United States Treasury Fraud Scam!

http://800notes.com/forum/ta-de071afa5bd5041/dangerous-new-trend-in-irs-scams

http://www.irs.gov/uac/Tax-Scams-Consumer-Alerts
http://www.treasury.gov/tigta/contact_report.shtml
http://800notes.com/forum/ta-8c2f64bf2b91fa5/irs-warns-of-telephone-scam

http://bigstory.ap.org/article/4b849c65e54346 ... leader-irs-scam

Report the Calls to the real IRS here:
•report the incident to the Treasury Inspector General for Tax Administration at 800-366-4484.
•You can also file a complaint with the Federal Trade Commission at FTC.gov. Add "IRS Telephone Scam" to the comments in your complaint.

To file complaints on Foreign company's and scams:
http://800notes.com/forum/ta-d20d86fdc3e145c/reporting-international-scams
https://www.econsumer.gov/#crnt
eConsumer.gov: Report Your Complaint
E-mail: econsumerwb@ftc.gov

This message is intended to contact you regarding an important action executed by the United States treasury intended your dearest attention.  Ingnoring this will be an intentional second attempt to avoid an appearance before a judge magistrate or grand jury for federal criminal offense.  The number is 4073370389.  I advise you to call and help us help you.