WASHINGTON: A French couple died while hiking in the New Mexico desert but authorities rescued their nine-year-old son before he too succumbed to the heat, officials said Friday. David Steiner, 42, and Ornella Steiner, 51, both from the town of Bourgogne near Reims, had been hiking in the White Sands National Monument on Tuesday afternoon when they apparently died from heat exhaustion, Otero County Sheriff’s Detective David Hunter said. “They underestimated the elements,” Hunter told Agence France-Presse, adding that autopsy results were still pending. Park rangers found the mother first while on a routine patrol. They checked her camera and saw that she had been with two other people, Hunter said. Authorities followed her tracks and found the body of the father, with the son nearby. He was dehydrated but responsive and was taken to a local hospital for treatment.