Investigators are honing in on new details amid the ongoing search for Savannah Guthrie's missing mom, Nancy Guthrie. Pima County Sheriff Chris Nanos told CBS News on Monday, February 16, that investigators believe the clothing and face mask worn by the person in the images released last week were purchased at Walmart. The outlet reported that authorities are still working to identify the brand. CBS News previously reported that the backpack of the person in the photos was a black Ozark Trail Hiker, which is sold exclusively at Walmart.