IRS scam. Claims I'm being sued and this is my last warning. IRS will never call you directly. Call blocked. Filed a complaint with TIGTA at https://www.treasury.gov/tigta/contact_report_scam.shtml
Same thing happened to me. Got a voicemail from robocall stating I was being sued by the IRS. I called the number back and the "agent" who identified himself as "Steven Smith" stated there was a warrant for my arrest because I owed $5000 in back taxes, which is BS. Got a call from the same number 2 hours later. The number is now blocked.
I just had a very terrifying situation. I got a voicemail (my first) saying this was a "final" notice about an IRS fraud investigation. I called. It seemed very fishy. I asked who I was speaking to, and was told "Daniel Brown," even though he had a VERY heavy accent and I was hearing a million accented voices behind him as in a phone bank. I looked up the number and it didn't match any IRS numbers. Still, I was concerned. He said my records from 2009-2014 were being audited, that I'd failed to fill out change of address forms, and that I had left out information on my 2010 forms, and that I owed $5000. Said they'd sent certified mail to an old address (my mother's), that they had evidence of adequate notice served. Said that I had to pay at least $500 immediately, right now, over the phone, that there was a WARRANT out for MY ARREST and that if I didn't resolve the matter during this phone call that a policeman would come to my home or workplace today.
Apparently this is a commonly repeated scam, that previously has cost over 5 million in false payments, likely from terrified people like me. I almost fell for it.
If you receive a similar call, report it to TIGTA.