724-134-5678 is a scam do not answer

I answer one call. They said they were calling for "Jason Jones" and was he here.  I told them there was no one by that name here, that my phone is a pre-paid cell - which it is - that I had no idea who this "Jason Jones" was or how they got my number and to never call here again. Then I hung up the phone.  A few minutes later it rang back from this number again. I usually don't answer these calls and won't answer this one again but this time I did pick it up again - intending to tell the woman calling that if she called a 3rd time I was turning the call over to the FBI but as soon as I picked up, the call disconnecetd. I think hanging up on me was the sole prupose of calling back again.  Who are these people?