Investigators in Arizona are focusing on a vacant residence as a potential staging site while searching for Nancy Guthrie.The 84-year-old mother of Savannah Guthrie was last seen at her Tucson home on the evening of January 31.The Pima County Sheriff and the FBI are analyzing DNA samples and evidence of a Wi-Fi jammer found at the property.The Guthrie family and the
FBI have provided a combined reward of 1.05 million dollars for information on her location.