Same. States to be from the Federal Treasury and that if you don't call back, legal action will be taken. Never claims what it is you did wrong, how long ago it was, or even have some kind of confirmation on your action or who reported it.
Had another number that sounds suspiciously like the same guy who called me months ago for 'tax fraud' and to contact him because there was a warrant out for my arrest. It has been about 7 months now, and I have have seen nothing from this.
Second time this morning, left another threatening message. The phone reception was not clear through the entire message, but well enough to get the jest.