IRS Scam
Scammers know that when someone receives a phone call from a government official, they get nervous even if they haven’t done anything wrong. This innocent person almost fell for an IRS scam when he received a call stating that he owed hundreds of dollars and that he would be arrested if he didn’t send them the money.
The scammer then made the mistake of saying something like “What are you prepared to do about this?” which rang alarm bells in the OP’s head. He was smart enough to tell the fake IRS officer that he would review his situation and call them back. The scammer cursed him and hung up but others may not have the presence of mind to do the same.