The FBI said on Thursday it was increasing the reward for information leading to the location of Nancy Guthrie, the mother of TV news anchor Savannah Guthrie, to $100,000 from $50,000.
The agency also released new visuals, including photos of a backpack the suspect could be seen wearing in video footage, and an updated description of the suspect following "forensic analysis" of footage from a doorbell camera.
The suspect was described as a male, between 5-feet 9-inches and 5-feet 10-inches and was seen wearing a black, 25-liter backpack, the FBI said in a statement. The agency identified the backpack as an Ozark Trail brand Hiker Pack.
Nancy Guthrie, 84, was first reported missing on February 1 in Arizona.
Guthrie's disappearance has captured the nation's attention with the FBI saying it had received over 13,000 tips from the public.
The Guthrie family, including NBC "Today" co-anchor Savannah Guthrie and her siblings, has released multiple videos pleading for their mother's return.
"We believe she is still out there," Savannah Guthrie said on Tuesday in a post on Instagram with video footage of the suspect at her mother's home. "Bring her home."

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