NEVADA COUNTY, Calif. — A tragic avalanche near Castle Peak has claimed the life of a 42-year-old man, while the remaining members of his snowmobiling group were found safe. The deadly incident occurred Monday afternoon in a remote backcountry area, highlighting the serious risks that remain even for experienced winter recreationists.

According to the Nevada County Sheriff’s Office, the avalanche was triggered around 2:20 p.m. as a group of five snowmobilers was leaving the Castle Peak area. Officials said the slide occurred on the backside of the mountain, an area known for steep terrain and unpredictable snow conditions. All five riders were described as experienced and properly equipped for backcountry travel.

One member of the group, identified as Chris Scott Thomason, 42, was caught in the avalanche and buried beneath the snow. Authorities said Thomason’s fellow riders immediately began digging him out using their avalanche safety gear. They also started emergency medical care as soon as he was located, working quickly in a race against time.

An additional group of three snowmobilers arrived to assist with the rescue efforts. Among them was an off-duty Truckee Fire medic who took charge of providing advanced medical aid. CPR was administered once Thomason was freed from the snow, but despite determined lifesaving efforts by friends and Good Samaritans, he did not survive.

Officials said Thomason and two others in the group were visiting from Bend, Oregon, while the remaining two riders were locals familiar with the Castle Peak area. The sheriff’s office noted that all five snowmobilers were well-prepared for the conditions and were carrying proper safety equipment, including avalanche beacons designed to help locate buried victims.

At the time the emergency call was received, Nevada County Sheriff’s Search and Rescue teams were already assisting with a separate missing person case in Placer County. Due to the seriousness of the avalanche, teams quickly redirected to Castle Peak. Tahoe Nordic Search and Rescue also responded, deploying three SnoCats, three snowmobile teams, and several ski teams. A request for emergency helicopter support was made, but air resources were unavailable. In a statement, the sheriff’s office thanked nearly 50 responders, along with Thomason’s four friends and three Good Samaritans, for their heroic efforts in an extremely dangerous situation.