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.
This number came on with the usual IRS THREATS we have all heard before repeatedly. This time, the call went through to people with the typical foreign accents. I told them they are scammers and to stop calling my number. I am tired of them waking the baby and upsetting the dog. They stopped the polite nonsense and began to scream they will come kill my dog.
Listen I dealt with the IRS and they usually contact you by certified mail! I was called about owing and found this to be a scam, which I will report to the IRS.