Just found a prerecorded message on my answering machine. Same IRS/arrest warrant spiel described by others. Enough unusual wording/spacing to sound like "English-as-a-second-language." End of message made me laugh: "Thank you and have a great day."
They said they are the "internal revenue services" and that a warrant has been issued for my arrest. They asked why I am scared. I said I am not scared but I played along and they said I have been filing my taxes incorrectly for the past five years and that I owe $4980. When I asked where they are located they hung up.
They are impersonating an IRS Federal Officer, they say an arrest warrant has been issued and they are trying to contact you. My landline is on the Do Not Call List.