got a call from 202-241-1311 from a man with thick indian, hindu, or pakistan accent claiming to be with IRS. He said his name was Mark Cooper and stated his badge #. He said he was with the tax audit department with IRS and a warrant has been issued for my arrest.  He said I must call him back to have the arrest warrant stopped before it's too late. This is an aggressive phone scam. Do not give them any info. Instead, report them to IRS and FTC. You can see this is a scam directly on IRS website.
http://www.irs.gov/uac/Tax-Scams-Consumer-Alerts

The guy just tried this on me left a voice mail. Heavy indian accent. He is officer mark with the IRS treasury department and says a tax lawsuit and federal tax lien has been filed against me in court. Stated I needed to call him back about this urgent matter. I know for a fact I have no situation which would result in this red flag #1. Then I called the number back blocking my own number. There is a very poorly made fake IRS recording done on an answering machine with bad echo on the recording. It tells you to pick option 1 or 2 after the made script it has. If you pick nothing it just hangs up and ends the recording which the real IRS and Treasury department systems would not do Red flag #2. Then found this scam on the IRS website red flag #3. I am going to pass this along to a few more agencies I know that handle this stuff. Everything I have found so far says this is a scam.

Just got the same thing from the same number. First from Lisa Johson ; then I called back , got the fake recording and Mark Cooper answered me. Threatened about an arrest and that I should be ready to have the cops on my door and I should get a criminal atorney.  I reported the incident to ftc.gov