This is some coward hiding behind a magicJack device plugged in at some God-forsaken corner of the world where there is Internet service. He's no better than a common criminal using a magicJack device and your fear the same way a common thief uses a toy pistol hidden in the pocket of his overcoat to make a bulge that looks like a real gun.
You can verify that this is a magicJack number by searching for it at http://www.phonevalidator.com .
MagicJacks are readily obtainable outside of the United States for about $100 US and can come with up to a year of free calling to the U.S. and Canada. In India, see, for example,
http://magicjack.in .
So it doesn't take long to turn a profit, even if only 0.1% of the people they call are naive enough to fall for their scam.
In addition to the regular reporting channels, e.g., the FTC and/or your local state attorney general's office, you might also report the abuse to YMAX Corp. YMAX Corp. is a wholly-owned subsidiary of the company that sells magicJacks and is responsible for assigning phone numbers to them. I have seen reports that they are pretty good at responding to complaints and may be able to permanently shut off a magicJack device, if necessary, so that it can never be used again.
The YMAX Corp. main web page is at:
http://www.ymaxcorp.com
and their site giving information on how to lodge a complaint is at:
http://www.ymaxcorp.com/contact.html
Note that the "contact" website gives a clickable link to a "live chat" where you can make your complaint.