These people tried to convince me that federal marshals were coming to get me unless I call them immediately. No explanation was given, just that they were coming to arrest me.

Left a message:  "To know your case number and speak with a Federal Agent, call back on (315) 207-4321."

... your serious attention. Ignoring this will be an intentional second attempt to avoid initial appearance before a magistrate judge or grand jury for a federal criminal offense. Now, this is the final attempt to reach you. To know your case number and to speak to a federal agent called back on 315-207-4321 I repeat 315-207-4321. Thank you. Different voice: thank you for your time. You will not be contacted again.

Calling the number given results in reaching thisan answering machine that is not taking messages because it is full.

Called, Brain Walker, badge # 100381 call me asap, 315 207-4321, tax audit for the years of 2007-2014, for mistakes and miscalculations.   SCAM!!!  IRS will not call you, they will mail a letter. Never contact by phone.

It starts mid-sentence: "your serious attention. Ignoring this will be an intentional second attempt to avoid initial appearance before a magistrate judge or grand jury for a federal criminal offense. Now, this is the final attempt to reach you. To know your case number and to speak to a federal agent called back on 315-207-4321 I repeat 315-207-4321. Thank you. Different voice: thank you for your time. You will not be contacted again."