I got a phone call from this number saying I had a warrant out for my arrest. And then they just hang up.

I let it go to voice mail and there was an automated messaging saying that if I didn't call back there would be a warrant out for me and I would be arrested that night. They said they were from the IRS. When I called back it just rang and rang until it was answered by a someone who wouldn't tell me who they were when I said I received a call from this number and wanted to know who they were.