US Dept of Treasury called and left a message--the voice was computerized and foreign. When I called back, there was a voicemail and the man spoke with an accent.
They act like your being prosecuted for IRS tax fraud and ask for info. They asked me if I have a criminal lawyer, they also told me they tried mailing documents on this matter twice and the mail got returned. All they knew was my phone number and name. I'm glad I googled the phone number. Anyone with a real case will send it via email or by letter upon your request. You will have evidence against a scam in writing or email.
Don't pay any attention to these bogus messages, and threats. If you've gotten nothing in the mail pertaining to what they're calling about, there's likely nothing to worry about. You don't answer unknown numbers in any way, you'll hear nothing from these fools. Their motive is to scare you into thinking you've got a phony debt out.