Law enforcement officers investigating the disappearance of 84-year-old Nancy Guthrie, mother of NBC “Today” show host Savannah Guthrie, have set up a roadblock near her Tucson, Arizona home as part of the ongoing inquiry into her disappearance.

According to the Associated Press, authorities sealed off a rural road about 2 miles (3.2 km) from Guthrie’s residence late Friday night, with sheriff’s vehicles, FBI units and forensic teams moving through the area. The Pima County Sheriff’s Department confirmed the activity was connected to the case but declined to provide specific details about the operation.

Nancy Guthrie was reported missing on February 1, and investigators have been working with federal and local agencies to unravel the circumstances of her disappearance. Blood matching her DNA was found on the porch of her home earlier in the investigation, and purported ransom notes were sent to media outlets, though deadlines associated with them have now passed with no contact.

The intensified law enforcement presence comes amid a broader effort to follow leads, collect evidence and canvass the area for additional clues. Authorities have reviewed surveillance footage, processed thousands of tips, and sent forensic samples for laboratory analysis.

Officials are working under heightened concern for Guthrie’s well-being due to her age and medical needs, including reliance on daily medication and treatment for heart conditions. The investigation continues without further specifics released to the public.