Started speaking before the answering machine finished its greeting. Caller was difficult to understand. I could, however, distinctly hear the words, "US Treasury" and the threat that if I didn't call back, it would be a violation and would require an appearance in front of a magistrate judge or federal grand jury for criminal offense.

I literally just got this exact same call too. Some weird scammers, sounded foreign.

...US Treasury... enforcement action... blah blah. Just another scam, move on.

me too! same thing

treasury department, dept collection