I've been receiving calls from this organization (I say that loosely) who claim to be representatives from the IRS investigations division. When asked to speak to a supervisor, they hang up. They always call from a different phone number, but it's always the same recording and similar sounding voice that answers when I call the # back. I've told them I want my number removed from their calling list and they hang up.
Fake IRS robocalls saying a lawsuit is being filed against you. Telling you to call this number for info. Same number the robocall is initiated from. Answering machine screens all my calls. These calls stop once you pick up and hang up right away on one of the calls. Got 3 calls in one day from 3 different numbers before I did that.