My father and my aunt both had this same exact scam happen to them yesterday...within hours of each other.  They some how have access to people's account because he actually called comcast and requested that they cut my aunt's cable service because he said they'd be traveling.....so my aunt saw her tv wasnt working and he called her telling her that her payments hadn't been going through.  
He gave her his phone number and also the name he used was Victor Gonzalez.  He described her house to her and told her HER last four of her social AND her Comcast account number.  So he definitely has inside information from Comcast and they need to so some kind of investigatino from their end either from a current or disgruntled former employee who is stealing customer personal information.