This has been going on for some time. The IRS does NOT contact you by phone. This is an international group of scammers. About two years ago a wave of arrests in Florida and in India shut this down, but it appears that they are back.
I got my scam call and knew it was fake immediately because I live in Pennsylvania and the call came from a San Bruno, California area code and exchange.
I have never picked up the phone on any of these.
I must be in so much trouble, oh my.
Others are the Windows is expired one, the we need to contact you about your credit card (I dont do credit cards), somebody is doing illegal things with your SS number and call or the police are coming over.
There are more, just cant remember right now.