Search for Nancy Guthrie expands after 20 days

NOT RULING OUT THE POSSIBILITY THERE'S MORE THAN ONE SUSPECT. POSSIBILITY THERE'S MORE THAN ONE SUSPECT. KELLY O'DONNELL HAS. MORE THAN ONE SUSPECT. KELLY Y O'DONNELL HAS THE LATEST. KELLY O'DONNELL HAS THE LATEST. >> R Reporter: DAY 20. THE LATEST. >> Repororter: DAY 20. THE RIBBON ON THE LAMP. >> Reporter: DAY 20. THE RIBBON ON THE LAMP POST, A A MARKER FOR. THE RIBBON ON THE LAMP POST, A MARKER FOR WHERE IS NANCY. POST, A MARKER FOR WHERE IS NANCY GUTHRIE. WHERE IS NANCY GUTHRIE. TODAY THE ARIZONA. TODAY THE ARIZONA ATTORNEY GENERALAL REMAINS ENCOURAGED. ATTORNEY GENERAL REMAINS ENCOURAGED. >> I CERTAINLY DON'T. REMAINS ENCOURAGED. >> I CERTAINLY DON'T CONSIDER IT A COLD. >> I CERTAINLY DON'T CONSIDERER IT A COLD CASE YET. CONSIDER IT A COLD CASE YET. THIS IS A ONGOING, CASE YET. THIS IS A ONGOING, VERY ACTIVE. THIS IS A ONGOING, VERY ACTIVE INVESTIGATION. VERY ACTIVE INVESTIGATIOION. >> Reporter: AN FBI. >> Reporter: AN FBI OFFICIAL TELLS NBC NEWS, SOSOME AGENTS AND. OFFICIAL TELLS NBC NEWS, SOME AGENTS AND ANALYSTS ARE BEING. NEWS, SOME AGENTS AND ANALYSTS ARE BEING ROTATED TOTO KEEP FRESH.

ANALYSTS ARE BEING ROTATATED TO KEEP FRESH EYES ON THE CASE. ROTATED TO KEEP FRESH EYES ON THE CASE. WHILE INSIDE THE. EYES ON THE CASE. WHILE INSIDE THE TUCSON FBI FIELD. WHILE INSIDE THE TUCSON FBI FIELD OFFICECE, THE COMMAND. TUCSON FBIBI FIELD OFFICE, THE COMMAND POST REMAINS FULLY. OFFICE, THE COMMAND D POST REMAINS FULLY STAFFED AND ACTIVE AND. POST REMAINS FULLY STAFFED AND ACTIVE AND WILL CONTINUE TO BE. STAFFED AND ACTIVE AND WILL CONTINUE TO BE.E. ACCORDING TO A SECOND. WILL C CONTINUE TO BE. ACCORDING TO A SECOND FBI OFFICIAL. ACCORDING TO A SECECOND FBI OFFICIAL. ACTIVE RIGHT NOW, FBI OFFICIAL. ACTITIVE RIGHT NOW, NEWLY SUBMITTED. ACTIVE RIGHT NOWOW, NEWLY SUBMITTED SECURITY VIDEOS FROM. NENEWLY SUBMITTED SECURITY VIDEOS FROM NEIGHBORS ARE BEING. SECURITY VIDEOS FROM NEIGHBORS ARE BEINING REVIEWED. NENEIGHBORS ARE BEING REVIEWED. CELL PHONE DATA AND. REVIEWED. CELL PHONE DATA AND DNA FROM THE CRIME. CELL PHONE DATA AND DNA FROM THE CRIME SCENE BEING ANALYZED. DNA FROM THE CRIME SCENE BEING ANALYZYZED. TODAY PIMA COUNTY. SCENE BEING ANALYZED. TODAY PIMA COUNTY SHERIFFS O OFFICIALS. TODAY PIMA COUNTY Y SHERIFFS OFFICIALS NOTED THEY DO NOT RULE. NOTED THEY DO NOT RULE OUT THE POSSIBILITY THAT MORE THAN ONE. OUT THE POSSIBILITY THAT MORE THAN ONE PERSON MAY B BE.

THAT MORE THAN ONE PERSON MAY BE INVOLVED. PERSON MAY BE INVOLVLVED. TUCSON CONGRESSMAN. INVOLVED. TUCSON C CONGRESSMAN ABLETA --. TUCSON CONGRGRESSMAN ABLETA -- >> THERE IS. ABLETA -- >> THEHERE IS COOPERATION AND. >> THERE IS COOPERATION AND COLLABORATION, AND. COOPERATION AND COLLABORATION,N, AND THAT'S GOOD NEWS FOR. COLLABORATION, AND THAT'S GOOD NEWS FOR THE GUTHRIE FAMILYLY AND. THAT'S GOOD NEWS FOR THE GUTHRIE FAMILY AND FOR NANCNCY GUTHRIE. THE GUTHRIE FAMILY AND FOFOR NANCY GUTHRIE. >> YOU FIND THAT. >> YOU FIND THAT REASSURING? >> ABSOLUTELY. REASSURING? >> ABSOLUTELY. WE WANT EVERYOYONE THAT. >> ABSOLUTELY. WE WANANT EVERYONE THAT HAS EXPERTISE TO BE. HAS EXPERTISE TO BE WORKING ON THIS CASE. >> Reporter: INCLUDING. WORKING ON THIS CASE. >> Reporter:r: INCLUDING A DIFFERENT GROUP WITH. A DIFFERENT GROUP WITH EXPERTISE. KNOWN AS THEHE SEARCHING. EXPERTISE. KNOWN N AS THE SEARCHING MOTHERS OF SA NORA. KNOWN AS THE SEARCHING MOTHERS OF SA NORA. THESE WOMEN SAY THEY. MOTHERS OF SA NORA. THESE WOMEN SAY THEY HAVE A PROVEN TRACK. THESE WOMEN SAY THEY HAVE A PROVEN TRACK RECORD OF FINDING. HAVE A PROVEN TRACK RECORD OF FINDING MISSING PERSONS BACK.

RECORD OF FINDING MISSING PERSONONS BACK HOME IN MEXICO.