FBI Searches for Nancy Guthrie Using Helicopter-Mounted Pacemaker Scanner

Investigators are utilizing a helicopter-mounted signal sniffer to detect the pacemaker of Nancy Guthrie after she vanished from her Tucson home.Pima County Sheriff Chris Nanos and the FBI are analyzing surveillance footage of a masked suspect wearing a Walmart backpack seen near the residence.A black glove found at the scene provided a DNA match that will be entered into a national database to identify the person responsible for the disappearance.The FBI doubled the reward to $100,000 for information as Savannah Guthrie remains absent from "Today" to focus on her mother's recovery.