Coconino County Sheriff's officials identified the victim Thursday as 16-year-old Kreg Harrison Jr., of St. George.
They say Harrison was visiting Supai Canyon at the bottom of the Grand Canyon with his Boy Scout troop Wednesday afternoon when he apparently drowned while swimming below Mooney Falls.
Authorities say Harrison was with three other scouts when he tried to swim underneath the falls and got caught in the undercurrent.
Harrison was pulled to shore, but authorities say attempts to revive him by CPR were unsuccessful.
His body was taken to the county Medical Examiner's Office to determine the cause of death. Bureau of Indian Affairs police officers are assisting in the investigation into the teen's death.
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