United Investigations Tried to collect money for an outstanding debt to invalid loan co., and threatened jail if not paid. unknown, Nationwide

Did they have thick accents? If so they are just scammers - tell them to kiss your a$s and hang up.

The next time he calls tell him that a hex has been put on him. They believe in this stuff

Even if this for a legitimate debt, you should never conduct business with any collection agency that uses such illegal activities. If you did pay them they'd just come right back for more money.

 Send/fax the collection agency a letter via Certified Mail + Return Receipt (do NOT use regular mail) stating:

Per the Fair Debt Collection Practices Act, cease all communications with me. Receipt of this letter is officially being time stamped via Certified Mail. I will pursue each subsequent phone call from your office with a $1,000 per incident penalty for Fair Debt Collection Practices Act violations.  
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If they keep calling, read the following statement to them:
 
- Be advised that this call is being recorded. If you do not consent to being recorded, you need to terminate this call. Continuation of this phone call after officially being informed that it is being recorded implies consent to be recorded. This recording will be used to pursue Fair Debt Collection Practice Act violations in a court of law.

I'll bet there are hundreds of these posts on this site. These calls are from, mostly, India. The best way to handle them is to get caller ID, unless you already have it and ignore numbers you don't recognize.

This being a civil case and not a criminal case, they can't include the police. It's a scam to collect money from  people.
One way to handle them if you want to waste your time talking to them, is to tell the caller, he or she is being tape recorded and to be very careful what they say. I canjust guarantee they won't call back!