A 67-year-old man hiking in the Grand Canyon National Park died on a trail while hiking in extreme heat, which possibly caused hazardous conditions. The Grand Canyon National Park Service said that at about 11:50 a.

The NPS recommends avoiding hiking the Grand Canyon's inner trails between 10 a.m. and 4 p.m., when temperatures are at their peak. Temperatures in the inner canyon can reach over 120 degrees Fahrenheit in the shade, creating "extremely hazardous conditions for hikers," the NPS said.

An investigation is underway following the death of a hiker in Grand Canyon National Park.