A week later that same inmate provided more information to authorities about Capone, saying that he had talked about how you go about burying a body, describing how you have to make allowances for the body to sink into the ground. He mentioned how law enforcement had searched the 40 acres around a cabin in St. Maries; Capone said they could search for 50 years but would never find anything.

When other inmates teased him about Anderson's body being found at the cabin, Capone got up and left; the inmate walked with him and overheard Capone say, "I buried the body so deep they'll never find it … they'll never find the f***ing b***h."

Finally, Capone related a story about a book he had read where a girl named "Rachael" gets drugged and thrown into a lake. Capone said that was no way to dispose of a body because in the story the body floated up to the surface of the lake.

Capone told his fellow inmate that the night Anderson disappeared on April 16, she had showed up with a six pack of Grolsh beer. He said she had threatened to turn him because he was a felon in possession of firearms and he knew he would go to prison if he were caught. Capone admitted putting a sleeping pill in her beer "to shut her up," telling the inmate that he decided he had "no choice" but to "end it all."

To date Anderson's body has never been found.

Mia Carlson / KZBG contributed to this report.