Sheriff’s officials in Arizona have released two alleged ransom notes connected to the disappearance of Nancy Guthrie, mother of Today presenter Savannah Guthrie, in an effort to generate new leads. Investigators hope that someone familiar with the writer’s language or circumstances will identify the person responsible, despite possible personal or safety concerns that may have discouraged them from speaking out.

Nancy Guthrie, 84, disappeared from her home near Tucson on 1 February and the FBI is treating the case as a kidnapping for ransom. The first note, sent the following day, demanded $4 million in bitcoin and claimed she was safe but frightened; a second note, sent to a Tucson news outlet on 6 February, claimed she had died soon after being taken and had been buried “in nature”. Her family is offering a $1 million reward for her return.