GRAND CANYON NATIONAL PARK, Ariz. (AP) -- The National Park Service says a 67-year-old Arizona woman has died while on a private rafting trip in the Grand Canyon. Grand Canyon National Park spokeswoman Kirby-Lynn Shedlowski says officials were called at midday Wednesday about the death. The Flagstaff woman's name is being withheld until relatives are notified. The Mohave County Medical Examiner is conducting an autopsy to determine the cause of death. Shedlowski said she had no other details.