Mexican volunteer group conducts new search for Nancy Guthrie following anonymous tip

An independent search is underway for Nancy Guthrie's remains near the U.S.-Mexico border following an anonymous tip about the whereabouts of her body, though authorities say there is no evidence to verify the claim.

The Mexican volunteer search group Buscando Corazones Nogales told local media it coordinated the search with local authorities.

In a post on social media, the Pima County Sheriff's Department said it is aware of the reports regarding the anonymous tip, but said it was not contacted by Mexican authorities.

"This investigation remains active and ongoing, and we will continue to follow up on any credible information," the sheriff's department wrote.

Mexican authorities say there is no evidence to support a search in the city of Nogales. "There is no evidence, information, or objective elements suggesting that U.S. citizen Nancy Guthrie entered, remained in, or traveled through the state of Sonora," officials said.

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"Today" show host Savannah Guthrie is speaking out in her first interview nearly two months after her mother, Nancy Guthrie, was kidnapped.

"The verification carried out by the Prosecutor's Office has not uncovered any information, even of a preliminary nature, to support an investigative line related to her possible presence in the state," the attorney general of the Mexican state involved said. "As a result, the claims made by representatives of the search collective currently lack verifiable supporting evidence."

In another update on Thursday, the sheriff's department said 54-year-old Alexander Zabel Jr. was arrested in front of Nancy Guthrie's home following several complaints about his behavior. He was reportedly livestreaming from outside of the residence at the time of his arrest, and a sergeant with the department was knocked to the ground during the attempt to take him into custody.

Authorities say 84-year-old Nancy Guthrie, the mother of "Today Show" host Savannah Guthrie, was abducted from her Tucson, Arizona, home in the early hours of Feb. 1. They have released surveillance images from outside Nancy Guthrie's house, but the person who took her remains unidentified.

In an interview last month, FBI Director Kash Patel said the FBI was shut out of the investigation for the first four days after her disappearance.

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Nancy Guthrie has been missing since Feb. 1. Authorities in Pima County have said they believe she was taken from her Tucson, Arizona, home

"For four days, we were kept out of the investigation," Patel said on Sean Hannity's podcast about the FBI's lack of involvement in the initial days of the Guthrie investigation. "The first 48 hours of anyone's disappearance are the most critical."

Patel was also critical of Pima County Chris Nanos for sending DNA samples to a private lab in Florida that has worked with the sheriff's office before -- instead of to the FBI forensic lab in Quantico, Virginia.

"We have Quantico, best lab in the world," Patel said, adding he had an aircraft "ready to move it immediately through the night."

He added, "I understand everybody's frustrations."

In a statement, the Pima County Sheriff's Office said it was aware of Patel's statements in the podcast interview but said there was no delay in coordination with the FBI.

Anyone with information is urged to call 911, the FBI at 1-800-CALL-FBI, or the Pima County Sheriff's Department at 520-351-4900.