"Fake arrest scam (from faker: "Tax dept or irs")  claiming arrest if you don't pay up a warrant. and your property is being monitored right now."

Why are these obvious scammers allowed to run free - isn't there a way to stop them in their tracks?

To the unwary taxpayer: Please do not be taken in by these scammers. THE REAL IRS NEVER, NEVER, NEVER CALLS you, the taxpayer. They WRITE AN OFFICIAL LETTER TO YOU FIRST AND PROPERLY IDENTIFY YOU (SS #) AND INDICATE A SPECIFIC ISSUE. YOU MAY THEN HAVE A REAL IRS AGENT'S NAME TO RETURN A REPLY LETTER OR CALL TO.