Nancy Guthrie, 84, was kidnapped on Sunday, Feb. 1.
The search is ongoing for 84-year-old Nancy Guthrie, the mother of "Today" show host Savannah Guthrie, who investigators say appears to have been kidnapped from her Tucson, Arizona, home in the early hours of Sunday, Feb. 1.
The FBI has released photos and videos of an armed person in a mask in front of her home, appearing to tamper with a security camera.
Anyone with information is urged to call 911 or the Pima County Sheriff's Department at 520-351-4900.
Click here for the detailed timeline of the investigation into Nancy Guthrie's disappearance.
The Pima County Sheriff's Department, in a statement posted to social media, said that "law enforcement activity is underway at a residence near E Orange Grove Rd & N First Ave related to the Guthrie case."
Authorities did not release any further details but said that because this is a joint investigation, at the request of the FBI, no other information is currently available.
The Pima County Sheriff’s Department blocked a residential street and conducted investigative activity that the department said related to the search for Nancy Guthrie.
Investigators worked in the rain while keeping the public at a distance.
A department spokeswoman declined to elaborate on the nature of the activity other than to say it was related to the Guthrie case.
A number of vehicles, marked and otherwise, converged on the neighborhood 2 two miles from Guthrie’s home.
-ABC News' Aaron Katersky
Investigators are working to identify DNA found at Nancy Guthrie's property, the Pima County Sheriff's Department said in an update on Friday.
"DNA other than Nancy Guthrie's and those in close contact to her has been collected from the property," the sheriff's department said. "Investigators are working to identify who it belongs to. We are not disclosing where that DNA was located."
Several gloves were found amid the investigation, with the closest located approximately 2 miles from Nancy Guthrie's home, the Pima County Sheriff's Department also said.
"Reports that a glove was found inside the residence or on the property are inaccurate," the sheriff's department noted.
DNA was recovered from several gloves and other pieces of potential evidence, and those DNA samples are now being compared to samples taken from associates of Nancy Guthrie, Pima County Sheriff Chris Nanos told ABC News Friday.
The sheriff said he is hopeful investigators are “getting closer” to solving the case.
“We've gotten DNA back,” Nanos said.
“They already have the genetic markers of those that we think had access to the home,” he said, including members of Guthrie’s family and household help.
“Now we have to go through and try to eliminate people," Nanos said.
Several gloves have been found throughout an expanded search zone within a 10-mile radius of Guthrie’s home, the sheriff said. No gloves were found at her house.
Investigators planned to return to Guthrie’s house as soon as Friday to take additional measurements from the front doorway, where the suspect lurked. They have estimated his height to be 5 feet 9 to 5 feet 10 inches, and now the hope is to determine the man’s weight.
“It is really about just taking that video and frame-by-frame and trying to get as much out as we can,” Nanos said.
Other investigators are trying to trace the point of sale of the backpack sold at Walmart the suspect was seen carrying.
Walmart declined to comment on whether it is assisting the investigation.
The individual detained earlier this week for questioning in Rio Rico, Arizona -- who identified himself as Carlos -- is not fully cleared even though he has been released and is under no law enforcement restrictions, the sheriff said.
“Nobody's fully cleared,” Nanos said. “He talked with us, he was cooperative.”
Nanos said the sheriff’s department and FBI are working side-by-side to find Nancy Guthrie.
“We're not giving up,” Nanos said. “If Nancy's out there, we're going to find her. We're not giving up.”
-ABC News’ Aaron Katersky
