The news from 7/22 release begins:
Grand Canyon, Ariz. – At approximately 7:20 p.m. on Tuesday, July 21, the Grand Canyon Regional Communications Center received a report that at least one young man, and possibly as many as three, were overdue from a backpacking trip at Grand Canyon National Park.
The young men are reported to have left on a trip to the Deer Creek/Thunder River area on Saturday after reading about the trip in a magazine. According to the reporting party, the father of one of the young men, his son had stated that he would be back on Monday but did not return. Further investigation revealed that there were as many as four young men in the hiking party. All are in their early 20s, and all are believed to be students at Northern Arizona University. It was also determined that this group did not have a backcountry permit." Read more....
Update 2 p.m. on 7/23: According to more breaking news from the Arizona Daily Sun, it appears there's one hiker missing, not three or four. The friends thought to possibly be missing also have been contacted. Read more here: Overdue Canyon Hiker An NAU Student
This is the young man they're looking for, NAU student Bryce Gillies:
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Anyone who believes they have seen Gillies since Saturday is encouraged to contact the National Park Service at 928-638-7805.