This is a phone scam. We received a VM at our office stating the Peter Johnson was calling from the IRS. ("Peter" could barely speak English!) The caller stated that my employer's IRS account had been marked for tax fraud and to call before the issue went to the "federal office" or he would be arrested.
THE IRS DOES NOT THREATEN TO ARREST YOU! DO NOT GIVE THEM ANY MONEY. Go to this site and report the call:
http://www.irs.gov/uac/Newsroom/IRS-Warns-of-Pervasive-Telephone-Scam