I received a call from this number couple of times from someone with a heavy Indian accent and supposed to be calling me from "Criminal Investigation department of IRS". Right away I realized this is a scam as first - why would IRS outsource to India. second - they would send letter instead of calling third - the number to call back was not toll free (I just can't believe IRS CI dept don't have toll free #)
I told the guy to **** off and hung up......Next time they calls, will have some interesting conversation that will make him hate his job :)