TUCSON, Ariz. (PulseWire) — Investigators are appealing to the public for home surveillance camera footage from specific dates leading up to the disappearance of Nancy Guthrie, the mother of NBC’s Savannah Guthrie, as they process thousands of tips in their investigation.

As of Thursday, authorities had not disclosed any significant progress in the case. Recent surveillance images of a masked figure on Guthrie’s porch the night she disappeared, along with increased police activity across Arizona, had initially sparked hopes of a breakthrough. However, a suspect detained for questioning was subsequently released.

On Wednesday, FBI agents were spotted scouring the desert vegetation around Guthrie’s Tucson-area home. They also conducted door-to-door inquiries a mile away in search of additional clues.

They had specific questions regarding any unusual activity on cameras from January 31 and the morning of February 1, shared Ann Adams, a neighbor near the residence of Nancy’s daughter, Annie Guthrie. They were checking if we saw anything suspicious since then.

Guthrie, aged 84, has been missing since February 1. Authorities believe she may have been taken against her will, as DNA evidence confirmed the presence of her blood on her porch, raising fears for her safety, given her reliance on medication.

Local reports indicated that the FBI is specifically requesting footage from the night of January 11, nearly three weeks before her disappearance. The request was pushed through alerts to users of the Ring doorbell app in the area.

During the search, investigators uncovered black gloves that are now subject to DNA analysis. Meanwhile, hundreds of detectives are dedicated to the case, which is expanding across the region.

Earlier this week, the authorities stopped a man near the U.S.-Mexico border shortly after releasing videos of a suspicious individual seen approaching Nancy Guthrie’s home. Despite initial concern, the man was released after several hours of questioning.

The FBI had released images of an armed suspect that appeared to tamper with the camera at Guthrie’s home at the time of her disappearance, though these images have not provided clear leads on what happened to her. Officials express hope that, despite the limited visibility of the masked individual’s face, someone in the community may recognize him.

Despite receiving more than 4,000 calls to the tip line in the last 24 hours alone, the investigation still remains challenging. Savannah Guthrie and her siblings have shown willingness to consider ransom, although the authenticity of any ransom notes or claims remains uncertain.

The investigation continues as authorities and family members hope for answers in this troubling case.