The 'Today' co-anchor's mother, 84, is still missing six weeks after she was kidnapped from her Tucson, Ariz., home.

The new theory comes as the FBI returns to the neighborhood with new questions for residents there.

A neighbor said she doesn't believe the suspect seen on surveillance footage acted alone.

One of Nancy Guthrie’s neighbors believes that the security gate at the front of the 84-year-old woman’s property offers a potential clue into her disappearance, suggesting that more than one person ...