Investigators working on the disappearance of “Today” show host Savannah Guthrie’s mother are consulting with Walmart management to develop leads because a backpack the suspect was wearing is sold exclusively at the stores, the Pima County, Arizona, sheriff said Monday.

Nancy Guthrie, 84, was last seen at her Arizona home on Jan. 31 and was reported missing the following day. Authorities say her blood was found on the front porch. Purported ransom notes were sent to news outlets, but two deadlines for paying have passed.

The Federal Bureau of Investigation released surveillance videos of a masked person wearing a handgun holster outside Guthrie’s front door in Tucson the night she vanished. A porch camera recorded video of a person with a backpack who was wearing a ski mask, long pants, a jacket and gloves.

Pima Count Sheriff Chris Nanos said in a text message to The Associated Press on Monday that the 25-liter “Ozark Trail Hiker Pack” backpack was the only clothing item that has been “definitively identified.”

“This backpack is exclusive to Walmart and we are working with Walmart management to develop further leads,” Nanos said.

The suspect’s clothing “may have been purchased from Walmart but is not exclusively available at Walmart,” the Pima County Sheriff’s Department said in a statement Monday. “This remains a possibility only.”

Investigators on Sunday announced that a glove discovered near the Guthrie home has been sent for DNA testing. The FBI said that it received preliminary results Saturday and was awaiting official confirmation. The development comes as law enforcement gathers more potential evidence and as the search for Guthrie’s mother heads into its third week. Authorities previously said they had not identified a suspect.

The FBI said the suspect in the surveillance footage is a man about 5 feet, 9 inches tall with a medium build.

Nanos said on Monday that members of Guthrie’s family, including siblings and spouses, are not suspects.

“The family has been nothing but cooperative and gracious and are victims in this case,” Nanos said in a statement.

Authorities have expressed concern about Nancy Guthrie’s health because she needs vital daily medicine. She is said to have a pacemaker and have dealt with high blood pressure and heart issues, according to sheriff’s dispatcher audio on broadcastify.com.

(AP)