U.S. authorities are investigating a Bitcoin ransom email linked to the disappearance of Nancy Guthrie, the 84-year-old mother of 'Today' show host Savannah Guthrie. The email demands millions in Bitcoin, includes a deadline, and contains threats. The Pima County Sheriff's Office is collaborating with the FBI to verify the email's authenticity, having upgraded the case from a missing elderly person to a suspected kidnapping. The email features a valid Bitcoin address and some on-site details, though authorities caution it could be a scam.