Nancy Guthrie, 84, has been missing since Jan. 31. Despite intense attention and a steady flow of tips, authorities have not named a suspect.

Weeks have passed without any sign of the 84-year-old grandmother in fragile health.

Volunteers recover a backpack near Nancy Guthrie's Tucson home in the area as the ongoing search for the missing 84-year-old continues into its fourth week.

Google disputes critical search evidence in Nancy Guthrie case, raising questions about FBI leads while investigation continues with DNA and surveillance analysis.

DNA evidence found inside Nancy Guthrie's home could take nearly a year to be analysed since there are several problems with what the police have found. Pima County Sheriff Chris Nanos revealed that ...