Another in a long series of threatening IRS scam calls. Called back the number, and as some moron kept saying "hello, hello, hello..." we heard a bustling idiot-filled boiler room operation in the background.
Once again, the IRS does not call you on the phone and they don't send email to collect what they're due. They use snail mail--registered letters and the like. Besides, you'll already know you owe the American government money if you do. They don't need to call you out of nowhere.