A missing woman, bloodstains and a masked intruder: tantalising clues but few leads in hunt for Nancy Guthrie

The disappearance in Arizona of the Today show host Savannah Guthrie's mother has captivated the nation

Nancy Guthrie disappeared from her Tucson, Arizona, home two weeks ago, setting off a potent chain reaction of federal and local criminal investigation, amateur sleuthing and public obsession that - so far - has resulted in neither the 84-year-old grandmother being located or anyone named as a suspect or, indeed, arrested.

It is a case that is both enthralling and baffling the American public, casting doubts on the ability of investigators to get to the bottom of the mystery that each day generates a fresh 24-hour news cycle - but seemingly little in the way of solid fresh leads likely to solve the case.