Capitol Peak near Aspen.

ASPEN — Three people trying to recover the body of a hiker on a Colorado mountain were injured Wednesday after being hit by a “massive rockfall” likely triggered by other climbers above them, authorities said.

The most seriously injured Mountain Rescue Aspen member on Capitol Peak was flown to a Denver-area hospital for emergency surgery, after a rock knocked the rescuer “roughly 20 feet (6 meters) through the air in a ‘rag doll,’ or somersault motion,” the Pitkin County Sheriff’s Office said. The other two members were treated and released from the hospital in nearby Aspen.

The incident delayed the recovery of the body of Kelly McDermott of Madison, Wisconsin, which was spotted by a search helicopter earlier Wednesday. McDermott had been reported missing after failing to return from a climb of the 14,137-foot (4,309-meter) mountain on Sunday.

His body is located in a precarious spot about 500 feet (152 meters) below the Knife Edge, a ridge which leads to the final climb to the mountain’s summit. Because of the location, it may take some time to recover his body, Undersheriff Alex Burchetta told The Aspen Times.