Right now, an urgent and deeply unsettling search is underway in Arizona.

84-year-old Nancy Guthrie, the mother of today's show host Savannah Guthrie, has vanished.

And authorities say this is no longer being treated as a missing person case, but instead a crime.

In just hours, investigators escalated their response,

sealed off her home as an act of crime scene, and brought in homicide detectives. Yet, they are

refusing to say why. Today, we're walking through the full timeline. The official statements

and the critical details police

aren't explaining because in cases like this, what's left unsaid often matters just as much as

what's confirmed. Nancy is 84 years old, lives alone in Tucson, Arizona, and has three children,

including Savannah Guthrie,

anchor for The Today Show. There's also a daughter named Annie who lives near her mom in Arizona and a son, Cameron. Nancy became a widow at a young age. She was only 46 years old when her

husband Charles died of a heart attack at age 49. Savannah was just 16 years old when her husband Charles died of a heart attack at age 49.

Savannah was just 16 years old when her dad died.

Nancy never remarried, and the Guthrie clan is extremely close to their mom.

My mom is named Nancy Guthrie.

She had me when she was 29 years old.

I was her third baby baby and she always said,

when you came, I knew my family was complete. The word I used to describe my mom is noble.

She's strong like hard iron granite strong. We had some hard times when I was a child. You know,

we lost my dad suddenly and shockingly, and my mom was so strong and set aside her

own grief in many ways just to be there and make sure that we could all move forward together.

And I think that's the other thing I'd like to say about my mom.

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