A man was hospitalized after burning his feet on sand dunes at Death Valley National Park over the weekend amid scorching temperatures that reached up to 123 degrees.

The 42-year-old man was visiting from Belgium and was taking a short walk Saturday at Mesquite Flat Sand Dunes in California when he lost his shoes, the National Park Service said in a news release.

Although temperatures on Saturday reached around 123 degrees, according to the National Park Service, ground temperatures would have been much hotter. Officials said the man was wearing flip-flop sandals and it’s not clear if they broke or were lost in the sand.

The man’s family called for help and asked other park visitors to carry him out of the dunes to the parking lot. The man suffered third-degree burns on his feet, the park service said.

Due to the severity of his injury and the man being in pain, park rangers felt he needed to be transported to the hospital.

Because of the blistering heat, Mercy Air’s helicopter could not safely land in the park because the extreme temperatures reduced rotor lift, the National Park Service said. The man was instead transported by ambulance to a landing zone at a higher elevation and then airlifted to a hospital in Las Vegas.

The excessive heat has led to several deaths recently in state and national parks.

Park rangers at Death Valley encouraged visitors to stay within a 10-minute walk of an air-conditioned vehicle, drink plenty of water and avoid hiking after 10 a.m.