JASPER, Ark. (AP) — A 46-year-old Missouri man died after falling about 20 feet (6 meters) while hiking at the Buffalo National River in Arkansas, officials said Monday.

Brad Lee Thomas of Springfield was hiking with a group on Saturday in an underdeveloped wilderness area when he fell in the Indian Creek drainage, the National Park Service said.

The park service said that witnesses conducted CPR and rendered aid until rangers and first responders arrived. The officials then continued lifesaving efforts but were unsuccessful, the park service said.

Over the past month, rangers have responded to multiple hiking accidents in the Indian Creek drainage, the park service said. The park service said that in that area, the terrain is steep and the ground can be slippery.