Article continues below advertisementNancy Guthrie has been missing for nearly 100 days - but authorities are not letting up in their search for Today star Savannah Guthrie's mom. Arizona's Pima County Sheriff's Department released a statement on Monday, May 4, confirming it "remains fully committed to the investigation into Nancy Guthrie's disappearance.""This is an active and ongoing investigation, and we continue to work closely with our partners at the FBI," the sheriff's office said, explaining, "DNA and video analysis are underway, supported by laboratories across the country.