The hunt for missing Nancy Guthrie escalated on Friday night after investigators seized a vehicle and removed a camera from the roof of her home, hours after her alleged kidnappers sent yet another so-called ransom letter. However, details of the ransom letter were not shared by the authorities continued with their investigation.
FBI forensic teams were seen minutely examining the roof of Nancy's Tucson, Arizona home, where they reportedly found a camera attached to the house that had gone unnoticed during earlier searches. Investigators also towed away a dark-colored SUV from the garage, as authorities returned to the property for the third time since Nancy was reported missing on Sunday.
Possible Clues Found

More than a dozen vehicles arrived at the home over the course of the day, with forensic specialists, FBI agents, and sheriff's deputies all taking part in the operation. Authorities have not revealed what prompted the latest search, but it came just hours after a second message was sent to Tucson news station KOLD, allegedly from the people claiming to be holding the 84-year-old for ransom.
KOLD had earlier reported receiving a so-called ransom letter on Tuesday, as did TMZ. Officials say they are treating the messages as serious leads, though their authenticity has not yet been confirmed.

According to KOLD, the most recent letter did not include ransom demands or proof that Nancy is alive. The earlier messages, however, demanded millions of dollars in bitcoin in exchange for her release and set a final deadline of Monday.
Despite the growing intensity of the investigation on Friday, Pima County Sheriff Chris Nanos said he believes Nancy is still alive.
Nanos said both his investigators and the FBI remain hopeful that Nancy is still being held alive, adding that interviews with staff at her home have provided valuable information and helped move the investigation forward.
"What I believe is that Nancy was removed from her home against her will, and that we need to find her. That's what I believe. She's still alive," Nanos said Friday.
"I believe that I have no choice until something shows me, a piece of physical evidence shows me that that's different."
Cops Question Nancy's Staff
The sheriff said deputies have spoken with everyone who had recent contact with Nancy, including her landscaping crew, pool maintenance workers, a housekeeper, and an Uber driver who took her to her daughter Annie's home just hours before she disappeared.

"I think they have pretty much completed that," Nanos said. "We've talked. They've all been very cooperative. They provided certain information that was helpful to us."
Although Nanos struck an optimistic tone, he has also acknowledged that investigators are racing against the clock. The 84-year-old has ongoing health issues and is believed to be without her daily medications, adding urgency to the search.
In a new twist on Friday, authorities revealed they had identified a "vehicle of interest" that was reportedly spotted at a Circle K convenience store in the Tucson area. A spokesperson for Circle K told the Daily Mail that a tip led police to the vehicle, and said the company is helping the investigation by granting access to its surveillance footage.

Officials have not explained how the vehicle may be linked to Nancy's disappearance, nor whether it has led to the identification of any suspects.
The evidence collected on Friday represents the most significant breakthrough in the case since blood was found outside Nancy's front door shortly after she was reported missing.
After reports of the alleged ransom notes surfaced, Nancy's daughter, "Today" show host Savannah Guthrie, appeared in a public video alongside her siblings Annie and Camron, appealing directly to whoever may have taken their mother and urging them to make contact.
Questions about the authenticity of the ransom letters grew following the arrest of California man Derrick Callella on Thursday. Authorities say Callella sent fake ransom texts to Nancy's daughter Annie and her son-in-law, Tommaso Cioni, in what investigators described as a hoax.
Callella allegedly admitted he sent the messages to exploit the chaos surrounding Nancy's disappearance and possible ransom demands, telling investigators he was "just trying to see if the family would respond."

Officials believe his texts were separate from the messages sent this week to TMZ and Tucson station KOLD, one of which reportedly demanded millions in Bitcoin and set a 5 p.m. deadline on Thursday. TMZ also reported that a second, more serious deadline was set for Monday.
As of now, no suspects or persons of interest have been publicly identified. Still, President Donald Trump suggested Friday evening that the case is making meaningful progress.
Speaking to reporters aboard Air Force One, Trump said the investigation was going "very well" and that authorities "have some clues that I think are very strong."