Some scammer got himself a new number!  However, he didn't talk to me, so I can't give you much information.

Caller didn't leave a message but the last two times it was "the irs" threatening to sue me for money owed.

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

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.

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Do consider getting a call blocking device or phone.. You can google them and many are around $40.00 or so.If its a cell phone, some already have call blocking, if not, there are free apps on the web that will work for some. You can google this. If you have a smart phone, there is a free app called call control. Iphones appear to have apps also. Another one is called Mr. Number.

Fraud. Do not give them any information.

This number calls us numerous times.  We do not pick up.  However, they will ring for 12-15 minutes, evidently overriding our call answering service which should kick in after 5 rings.  Can anything be done to stop these people from calling us?