Savannah Guthrie's mother missing under suspicious circumstances

• The sheriff's department was notified of her disappearance around noon Sunday and subsequently launched a search-and-rescue effort.
• Nanos said his agency is treating the disappearance as a crime, based on "some things at the home that were concerning." He did not elaborate.
• Homicide investigators are working the case, Nanos said.

State of play: Nancy Guthrie has physical health conditions, including mobility issues that prevent her from walking more than 50 yards unassisted, but is of sound mind, Nanos said.

• "She did not leave on her own," he added.

Zoom in: Monday's "Today" show broadcast began with news of Nancy Guthrie's disappearance and a written statement from Savannah Guthrie and her family.

• "On behalf of our family, I want to thank everyone for the thoughts, prayers and messages of support. Right now, our focus remains on the safe return of our dear Mom," the statement said.

What we're watching: Nanos told reporters he was unaware of any threats made against Savannah Guthrie but said the sheriff's office has been in touch with her security team.

• Guthrie grew up in Tucson and attended UofA.

The bottom line: Anyone with information is asked to call 911 or contact the Pima County Sheriff's Department at 520-352-4900.