I have also received two calls within 12 hours from this number (415) 878-3780 stating that they were the IRS and the call was time sensitive and that I need to call before actions are taken. I did return the call and advised them by leaving a message that I have contacted my attorney and the call will be turned over to Home Land Security and to never call my number again.
Caller said their were from IRS and I needed to call immediately to resolve a IRS situation or they would take action. Google number to find others had been harassed by this caller.
I have received several call regarding the IRS issues, called back and got some response, when questioned them, they disconnect the phone. they keep calling.
Message left on July 29, 2015 around noon and again after 6 pm. Female said she was Mickey or Nicky Johnson from the IRS. Said her business and hotline number was 415 878 3780 and you have to return the call so they do not take action against you. Last comment on message was "Good -Bye and Take-care" Obviously a scam for Social Security numbers.