supposedly won $2.5 mill but had to pay $500

My mother-in-law received a phone call from a man in Jamaica (876-596-6522) he told her she won $2,5 million dollars but she would have to give them $500 then someone will  come to her door with a check and flowers. they asked her if she was over 65. then he said his name was John Williams and the number is coming from Kingston Jamaica. He asked  for a credit card number (we stayed on the phone to get as much information as possible) She then told him they were maxed out he then told her they will put $12,000 in a bank account and gave her an account number to us that money. He asked her to pay her credit cards only with the number the next day he told her to use a different account number and it was supposedly at  wells  fargo.