The Internal Revenue Service is warning about a new fraud involving the Electronic Federal Tax Payment System (EFTPS).

In this ruse, a con artist calls pretending to be from the IRS and demanding immediate tax payment, claiming two certified letters mailed to the taxpayer were returned as undeliverable.

Arrest is threatened if a payment is not made immediately by a specific prepaid debit card supposedly linked to EFTPS but actually controlled by the scammer.

To add to the fear, victims are warned not to talk to their tax preparer, attorney or the local IRS office until after the payment is made.

In another new fraud, scamsters are taking advantage of the partial information some people may have heard regarding the IRS hiring private debt collectors.

The IRS cautioned its authorized debt collecting firms will only be calling about a tax debt the person has had -- and has been aware of -- for years and that it would have previously contacted the taxpayer about the money owed.