The FBI released a description of the suspect in the disappearance of 84-year-old Nancy Guthrie, describing him as 5’9”–5’10” with an average build and carrying a black 25-liter ‘Ozark Trail Hiker Pack’ backpack.

The agency raised the reward to $100,000 for information leading to her location or the arrest of those responsible.

The Pima County Sheriff’s Department conducted searches near her home in the Catalina Foothills north of Tucson.

TMZ reported receiving letters from someone claiming knowledge of her alleged kidnapper, who said they were not being taken seriously, Fox News has reported.

The search has now entered its 12th day, with the FBI conducting extensive operations along multiple roadways in the area.