Nancy Guthrie Update: Sheriff Makes New Plea to Kidnapper

The ongoing search for Nancy Guthrie is now in its 18th day. Authorities continue to chase down leads and tips stretching into the tens of thousands as they look for the missing 84-year-old Tucson, Arizona resident.

On Tuesday, Pima County Sheriff Chris Nanos provided an update on the investigation in a news conference, during which he issued a clear message to whoever is responsible for Nancy's kidnapping.

'Just let her go'

Nanos said he has a team of 400 investigators currently in the field working the case, and they continue to do their jobs "with the hope and the belief that they’re going to find Nancy, and she’s going to be OK."

Nanos also directed a plea at the person or persons who are currently holding Nancy.

"Just let her go. It will work out better for you in the long run," Nanos said. "Take her to a park. Take her to the hospital. Just let her go."

Police undeterred, Nanos says

Despite experiencing a setback when glove DNA testing did not produce any matches in the FBI's Combined DNA Index System (CODIS) database, Nanos said he and his colleagues are not giving up.

"As long as we have the ability to chase a lead, it’s not cold," Nanos said Tuesday.

'We're not going to give up. We're going to find Nancy, and we're going to find out who did this."

Nanos also debunked a rumor that authorities had whittled down the suspect pool to roughly 40 people, calling it "not true."

Savannah Guthrie's colleagues pay tribute to her mother

On Wednesday morning, Today co-hosts Hoda Kotb, Craig Melvin and Carson Daly recognized coworker Savannah Guthrie's missing mother by wearing yellow ribbons and decorating the show's set with yellow flowers in honor of Nancy.

“We’re all wearing ribbons as we send our love to Savannah and her family,” Kotb said.

Daly also referred to Nancy Guthrie as "our missing mom" and Melvin said the group "remains hopeful” of a positive outcome.