OMG same thing happened to me. They gave me a fake case number and couldnt explain in details any of the violations she claimed i had done. When i wanted to get very specific, she hung up on me.
Woman called me and told me there was a warrant out for my arrest for tax evasion. When I asked for more details she said she had already confirmed them with me. She hadn't. Then I asked her to confirm the address that they previously sent information to, she couldn't. Then I told her I needed a number or to have someone call me back because I needed to go back to work. She told me that if the line went dead then she would forward my information to the police. Still waiting for someone to come arrest me. They'll be looking in the wrong area code if that is the case.