Same experience with me they became vulgar and abusive when I asked more about their claim. I'm calling them back and told them that I would like to make a payment so that I don't go to jail and they hung up. It sounds like a make-shift call center in India.
I had a voicemail from this number; 360-262-6428 on 10/7/15. I could hardly understand the message as the woman had a heavy Indian accent. When I dialed the number back I got a man with the same heavy accent. He told me to hold on while he "gathered my information". When he returned he told me he was calling on behalf of IRS and that due to miscalculations in our taxes from 2008-2012 we owed money. He also said they had contacted me by mail in Jan. and that because we didn't pay, the local police will be at my door within the next hour. At that point I laughed out loud at him and hung up. I proceeded to block the number. Total scam artists, I feel badly for the people who fall for this stuff.
Received 2 voicemails stating that if I did not respond to the call, I would be taken into custody. When I called the number, the man who answered stated "IRS investigations."