threateing calls

I had a call a week ago, threatening me if I did not call them back with in the next hour, that I would be arrested with in 24 hours. needless to say, nothing happen.  to day I could a call and I answered it, you could it was a Indian  gentleman  telling me there Law Firm was representing the IRS for tax evasion, for the amount of $3020.80 and if I did not pay it then there would be a warrant out for my arrest. {and very rude} but when I brought up about the week before. He say so you want to be arrest, and hung up.     People get arrested for all kinds of things in this country, We the people should have the right to sue these scum, if the government and law enforcement know about these people and they do. they should be butting them out of business.