Apparently a scam by someone claiming to represent the US Treasury. Left this threatening message: "I advise you to cooperate with us and helpers to help you. Thank you. "
This was apparently a recorded call advising me to call this number and threatening me with "serious consequences" unless I did. Called said something about an "impending legal action." Also said that if I ignored this call it would constitute my second and final notice before legal action. I did not answer.