They have called twice today.  It is a recorded voice claiming to be the IRS notifying me they have filed charges against me.  They said I should call them immediately to resolve the issue.  The number is now blocked.  It is a scam.  The IRS will never notify you via telephone.
I know of a number of people who have dumped their landlines because Telco companies do nothing to stem the barrage of scam calls.  And, I am considering doing the same.