The search continued for for a teenage boy from Tennessee and his grandmother who disappeared while hiking in Arizona.
Witnesses said Lou-Ann Merrell, wife of Randy Merrell — who helped found the Merrell Boot Co. in 1981 — and Jackson Standefer, 14, lost their footing Saturday during a family trip in the Arizona park and fell into the creek.
Jackson lives in Chattanooga.
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The National Park Service deployed a drone, helicopter and dozens of rescuers in an effort to find the pair. The drone footage must be analyzed for clues.
The park service said it's too early to determine what went wrong.
