“Today” host Savannah Guthrie on Monday released a new direct plea to the public, begging for help to find her mom, Nancy Guthrie, more than one week after the 84-year-old was abducted.

“We are at an hour of desperation, and we need your help,” Savannah Guthrie said in an Instagram video, speaking directly to the camera.  

“We believe our mom is still out there. We need your help,” she said. “Law enforcement is working tirelessly, around the clock, trying to bring her home.”

“She was taken, and we don’t know where, and we need your help,” she said. “So I’m coming on just to ask you … no matter where you are … if you see anything, if you hear anything, if there’s anything at all that seems strange to you, that you report to law enforcement.”

Savannah Guthrie thanked everyone for their prayers and love, and said she believes her mom is feeling those prayers, too.

The search for 84-year-old Nancy Guthrie began after she was abducted from her home near Tucson, Arizona, early on Sunday, Feb. 1, authorities said.

The exact time of her kidnapping is not clear. Nancy Guthrie’s doorbell camera disconnected at 1:47 a.m., Pima County Sheriff Chris Nanos said, and then at 2:12 a.m., the camera software detected a person. At 2:28 a.m., Nancy Guthrie’s pacemaker app disconnected from her phone, which was left behind at her house, Nanos said.

This weekend, faced with a demand for a bitcoin ransom and a Monday deadline by someone claiming to be Nancy Guthrie’s kidnapper, Savannah Guthrie and her siblings said they’d pay for their mother’s return.

“We received your message and we understand,” Savannah Guthrie said in an Instagram video this weekend. “We beg you now to return our mother to us so we can celebrate with her. This is the only way we will have peace. This is very valuable to us, and we will pay.”

The message Savannah Guthrie references in her new Instagram post is the same message the FBI and Pima County Sheriff’s Department said they were studying Friday, according to a source familiar with the investigation. Investigators have not confirmed the authenticity of the latest message, which was received by a Tucson television station, nor any of the other ransom notes mentioning Nancy Guthrie, according to the source.

As the search intensifies, a 5 p.m. Monday deadline set in an initial ransom note from earlier last week is the point of focus for authorities, though investigators are still not certain of the ransom notes’ authenticity and continue to pursue all leads, a source familiar with the investigation told ABC News on Monday.

Investigators have returned repeatedly to the home of Savannah Guthrie’s sister, Annie Guthrie, where Nancy Guthrie enjoyed dinner and a game night before returning to her home a few minutes away on the night of Saturday, Jan. 31.

Investigators have also returned to Nancy Guthrie’s home, where they’ve examined rooftop cameras, towed away a car and made inquiries of neighbors.

The sheriff’s department said it is “an active and ongoing investigation,” but added that “investigators have not identified any suspects, persons of interest, or vehicles connected to this case.”

Anyone with information is urged to call 911 or the Pima County Sheriff’s Department at 520-351-4900.

ABC News’ Nadine El-Bawab contributed to this report.