India, July 28 -- Pima County Sheriff Chris Nanos says the search for Nancy Guthrie is still active after Savannah Guthrie shared a new emotional plea nearly six months after her mother's disappearance.

Nancy Guthrie, 84, went missing from her home near Tucson, Arizona in the early hours of February 1. As per the FBI, the case continues to be treated as a kidnapping for ransom.

Pima County Sheriff Chris Nanos, who is leading the investigation, spoke to NBC affiliate KVOA News 4 Tucson on July 27 after Savannah's video came out. He made clear the case has not gone cold. "We still have DNA that's not just one lab or two labs," Nanos said, according to KVOA.

"These are labs all across the country that are talking to one another about how ...