The FBI is investigating the February 1 disappearance of Nancy Guthrie from her home near Tucson, Arizona, as a potential kidnapping for ransom after blood was found at the scene and surveillance video captured a masked individual. Multiple ransom notes, including demands for Bitcoin, were sent to media outlets, with some classified as extortion attempts and others remaining under review. The Pima County Sheriff's Department is also involved but has declined to comment on the notes.