This is a call-back number from 518-678-6412. The caller is part of a scam and phishing operation claiming to be the IRS. They often state that you owe "back taxes" or that there is a warrant for your arrest for unpaid taxes. They often post their number as a callback number in Craigslist ads in order to get your phone number and distribute it to their network of scammers and spam callers. DO NOT respond to it. DO NOT call it back. BLOCK it with a call-blocking ap if you have one.