New York Area code. They do seem to be aware of geographic location. First time I called from Nebraska area code and they denied being IRS or anything. However, after changing it to a NY area code and calling back they attempted the old scam we all know.
@drwat#43261 Nice discovery on the range of numbers!! I have reported all the numbers to Level 3 Communications. Their turn-around time is about 2 days to confirm and shut them down (might be 4 days since there is a weekend here and there is quite the range of numbers for them to verify.