Does non-payment of a payday loan means fraud

I was contacting from a company by the name of united national legal investigation, the man that i spoke with called himself Officer Williams, he stated that i owed $855. to a pay day loan company but he would not give me any information about the company or even the name of the lender, all he kept saying was that the companies 26 lawyers were ready to file a case against me for bank fraud and check fraud because i never payed back the loan, and my bank account has since been closed. during the time of the loan ireally needed it and had all intentions of repaying as i did before, my bank account was siezed for a 8yr old debt, so after i fixed that problem everything i had saved to pay off my loans were lost. the bank closed my account because i had insuffient fees that i wasn't able to pay off at that time, anyway, they loan company contacted me and we worked something out, i sent them two payments and they never contacted me again so i'm thinking its resolved this is back in february 08, but my main problem is that they are contacting my references telling them that they are responsible for the debt and thet will be going to court, they are telling me that they will come to my home or job to arrest me for fraud, i got so scared i hurried and bought a pre-paid card and set up payment arraingements, i've already sent them $380.,i still owe three more payments and now Mr. BRIAN O'CONNELL and Mr. Rick Mathers is calling me from the same company but a different number threatening me saying that Officer williams doesn't work for them and they don't have any evidence of any payments i made to them, and that i was going to jail, can some one please help me