Scam Artist called from this number saying I owe money.

I do not know who these people are or why they are calling me all the way from California.

I received a call from this number also and he left a file number but did not give the business name!!!

they claim they are untied credit management its bull crap

I received a call this morning threatening legal action.  Have no idea what this is about!!! He said he was an investigator and gave me a case number.  How can he threaten legal action when I have not received anything in writing?  These are not foreigners calling either!!!!