Same exact message left on my phone.  I do work on occasion for the FI & the dapartment of IRS is one of them.  I called a Special Agent that I know.  She told me #1 We don't call you. #2 We don't tell you we are sending an officer to arrest you #3 The IRS communicates through the USPS & it is not uncommon for it to come certified mail.  This is a hoax.  Simply block their number &/,or tell them you will contact the IRS yourself and handle anything dealing with the IRS directly.  When I did that they hung up on me.  They forget that not everyone scares very easy.  They come off sounding professionals even give you their badge #.  They are creeps preying on the elderly & people who don't know better.