MAMMOTH LAKES, Calif. — Authorities say a snowboarder has died in a fall on a backcountry trail near California’s Mammoth Mountain ski resort.

The Mono County Sheriff’s Office says someone called 911 Tuesday to report seeing a snowboarder tumble from a cliff in the southern Sierra Nevada.

Paramedics and firefighters hiked up and found 31-year-old Justin Khoshnevis dead. His snowboard was found nearby.

Officials say it appears Khoshnevis, a resident of Los Alamitos, California, fell while snowboarding alone along a ridgeline that is out of bounds from Mammoth.

The sheriff’s office urges skiers and snowboarders to travel with a partner when entering backcountry areas.