First responders rescued a 54‑year‑old man who suffered serious injuries in a fall Friday while hiking with a group in Trione-Annadel State Park, according to authorities.

Jerry Volttaorni lost his footing about 5 p.m. while hiking on a steep trail, according to a Sonoma County sheriff’s report. He tumbled over the side, falling about 15 feet. Part of the hill slid with him and his head struck boulders. Loose rocks then rolled on top of him, according to the sheriff’s report.

On Monday, Volttaorni remained in intensive care at Santa Rosa Memorial Hospital and was listed in serious condition, according to a hospital spokeswoman.

The group was hiking off the Spring Creek trail when Volttaorni fell, said Bennett Valley fire Lt. Travis Browne, who helped with the rescue.

Someone in the group called 911 on a cellphone with GPS capability, pinpointing their location.

Three Bennett Valley firefighters hiked about a half-mile to reach Volttaorni and the Sonoma County sheriff’s helicopter crew responded. A member of the hiking group was with him when responders arrived.

Firefighters found Volttaorni trapped in the rocks and bleeding heavily from a head wound. He also suffered scrapes and cuts and a possible spinal cord injury, the Sheriff’s Office said.

The rescuers pulled rocks off him and started medical treatment. The helicopter carried him to an ambulance waiting outside the park and he was taken to the hospital.

You can reach Staff Writer Randi Rossmann at 707‑521-5412 or randi.rossmann@pressdemocrat.com. On Twitter@rossmannreport.