An Arizona grandfather and grandson who went hiking in the desert near Gila Bend were found dead Thursday, The Arizona Republic reported.

A spokesman for the Maricopa County Sheriff’s Office said that Thomas Gillespie, 64, and Robert Miller, 12, were reported missing around 4:30 p.m. Wednesday by the boy’s mother after she had not heard from them in over 24 hours.

A manager from the hotel where pair was staying told authorities that he saw them head out on Tuesday around 9 a.m. He believed they were headed to hike and take photos of the Mormon Battalion trail, named after a part of the U.S. military during the Mexican-American War.

Deputies found Gillespie’s car around 5:30 p.m. Wednesday. The pair was believed to have walked about 5 or 6 miles before turning back toward the trailhead.

The spokesman said that Gillespie collapsed within a half-mile of the turnaround point while the grandson was found collapsed 1 1/2 miles from the trailhead.

When deputies discovered the grandfather and the grandson, neither had a phone, food or water with them. It was not clear if the pair started the hike with supplies.

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