These are scam callers posing as the National Crime Enforsement Agency.  They have East Indian or Pakistani accents and verbally threaten with criminal proceedings.  The calls are juvenille at best.  When I have returned the calls and confronted the so-called "National Crime Enforsement Officer," I have had responses of  yelling threats and lewd sexual remarks.  These scammers have called me from several different numbers.  As soon as I think they are gone for good, they start calling fagain from a different area code.  I am getting these calls because my information was hacked when I filled out a form on-line containing confidential information.  I have reported the calls to the FBI and Secret Service.  But I am told there is nothing they can do.  However, I was advised to file an identity fraud report with the local police department.  At this point, I'm going to change my phone number.  These scammers also leave messages on my phone extension at work.  My opinion:  if they have not been able to rip off your checking account, etc., with the informtion they have (e.g., the last 4 digets of your social security numberand/or the name of some company you've done business with) they are calling to scare you into giving them money.  DON'T.