The search for Nancy Guthrie going international.

Investigators have briefed border patrol agents and Mexican law enforcement authorities.

If you're the kidnapper crossing the border means you're creating a record of that movement.

Investigators are going into gun shops trying to match the unique holster.

More than 49,000 tips have been called it.

TMZ reporting they've received a new ransom demand.

This is a highly sophisticated demand.

Investigators are looking into genetic genealogy databases.

Authorities are now pulling data on every sale of that backpack statewide.

Has there been the evidence so far that Nancy is still alive?

There's been no evidence that she's not.

Good evening and welcome to a special edition of Laura Coates Live to search for Nancy Guthrie.

Tonight, investigators are making sure that no stone is left unturned and looking into the possibility that whoever took Nancy Guthrie may have fled to Mexico.

We're told law enforcement as brief Mexican officials to be on the lookout for any clues

about her disappearance. U.S. Border Patrol agents have also been briefed. In just a moment,

our reporters and FBI analysts will unpack all of the major developments from the day,

and there were quite a few. Nancy Guthrie's home is just about 68 miles from Mexico,

and now a Mexican nonprofit organization says it's helping with the search.

And listen to this.

The founder says a member of the Guthrie family directly reached out to them for help. But right now, investigators are still

working in the ground game in Tucson. They're combing through thousands of hours of video,

meticulously inspecting it frame by frame after canvassing residences, businesses, and government

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