These guys have sweat shops set up in India and elsewhere that do VoIP call forwarding so it looks like they are from the US but they are not. They have auto dialers to do DoS (Denial of Service) on companies and light up the entire switchboard. They are extortionists that are scaring people into sending money. We called the around, even the FBI, and nothing can be done. If you call the carrier from where this number originates, they will shut the number down but that is only an irritant for them and doesn't solve anything. All you can do is don't talk to them and they will get bored and move along.
My wife received a call from this number today and gave me the phone because they gave her my name stating that they were with the IRS. I have caller ID but still asked the person calling for a call back number. He provided me with (415) 251-3754 and requested I contact the agent in charge Kenny Webster asap regarding a law suit against me. Idiot didn't realize that I am a detective. The number comes back to a landline with a service provider of YMAX Corp possible Magicjack voip in Novato or Igancio CA. Don't fall victim to this scam and contact your local police dept and/or the IRS.
I just received a call from this number, answered, said hello and of course no one answered. Just an F.Y.I. People in other countries are dialing these numbers through a computer. They have software that can pick a random number in the U.S. that is not being used to dial to you. As previous bloggers have said, do NOT call the number back. Do not give ANYONE your information over the phone.
[As a footnote, this is along a similar line as the one ring phone scam to mainly cell numbers to try to get you to call it back. This scam has a "pay per minute" attached to it and you will pay through the nose if you even so much as call the number.]