I didn't answer a call from 714-535-7004 but they left the following voice mail.
We have been trying to reach you.  This call is officially a final notice from IRS Internal Revenue Services.  The reason of this call is to inform you that IRS is filing lawsuit against you.  To get more information about this case file please call immediately on our department number 323-522-5806. I repeat 323-522-5806.  Thank you.
I always save to my contacts scam phone numbers with the name SCAM and a circle/bar picture so I will recognize them when they call back. that way I don't need my glasses to read the number.

I didn't answer the call, but the following is a voice mail which is prerecorded message left in voice mail.
We have been trying to reach you.  This call is officially a final notice from IRS Internal Revenue Services.  The reason of this call is to inform you that IRS is filing lawsuit against you.  To get more information about this case file please call immediately on our department number 323-522-5806. I repeat 323-522-5806.  Thank you.

Last year, I had a different threat from someone saying they were from the IRS.  The IRS mails notifications first, which I reported to the FTC and will report this one too.

http://www.irs.gov/uac/Tax-Scams-Consumer-Alerts
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.

Another IRS Scam caller received from number 631-581-9211 (caller ID New York) indicating me to call number 323-522-5806 for futher suing information.

same as above. irs will mail not phone. that's been all over the news. exact numbers mentioned.

caution as well, I had a phone call from the police coalition asking for money. once I said yes they transferred me to a third party with a foreign accent. I hung up!.