I submitted my incident with the Dept of Treasury and got the following response:
This is a scam; the Internal Revenue Service (IRS) does not have anything to do with the individuals that are impersonating IRS employees. The IRS does not contact taxpayers via telephone demanding payment and/or threatening to arrest taxpayers. Do not provide any Personal Identifiable Information (PII) or money to these individuals. If you have suffered a financial loss or provided the caller with your PII please email or fax (202) 927-7018 your receipts, a brief summary of the incident and any other supporting documents that you have. Thank you for reporting this information.
Kept getting missed calls from this number. Finally picked up the phone and was cut off. I called them back and got a voice-mail. I didn't leave any messages, but a guy with a thick Indian accent called me back to tell me I'm under investigation. I told him I have never received any notices or been served with a subpoena and that he's out to scam innocent people out of their hard earned money and hung up on him. I reported incident to IRS online.
I'm fairly certain is Midland Credit. They have been harassing me and now to stoop to saying this is Joan Smith from the IRS, not Internal Revenue Service is crazy. I've had problems paying back taxes, but I am all good now so this is definitely a scam of Some debt collector. Wow.