Got a message from this number stating that this call is "officially a final notice from the IRS" and that "they are going to file a law suit against you". It's a total scam. If you actually had a problem with your taxes the IRS will contact you by mail first, not by phone.
I was left the same disgusting message as Sam stated above - from the IRS saying they are going to file a law suit against me - and this was my final notice -- I feel so badly for anyone who is scared into calling them back - - their give away to me was the statement "your final notice" which implies I have received prior notices which I have not, and the voice sounded like he was a hit man from the mafia which I can't believe the IRS would use that kind of voice, and we have never heard from the IRS in our 25 years of marriage so this type of call was not plausible at all.