LOS ANGELES (KTLA) — A skier has died after being found buried in snow amid blizzard conditions at Mammoth Mountain in the Sierra Nevada on Thursday.

Around noon, the mountain’s ski patrol responded to a report of an unconscious male skier who had been found upside down in deep snow, according to a Friday statement from Mammoth Mountain Ski Area.

Other resort guests were already working to dig the skier out of the snow when the patrol arrived. They began CPR and also used an automated external defibrillator on the down skier because he didn’t have a pulse, according to the statement from the mountain.

The skier was then rushed to Mammoth Hospital where he was later pronounced dead. Authorities have not identified the man, describing him only as a 52-year-old from Oceanside.

A cause of death was not immediately known but is “related to the snow in some way,” a Mono County Sheriff’s Office spokeswoman said in an emailed statement to NewsNation affilate KTLA.

No further details were provided about the incident. The Sheriff’s Office also reported Friday that a 55-year-old Michigan man died after being found unresponsive in a vehicle that was discovered buried in snow in a parking lot in Mammoth Lakes.

Mammoth Lakes, which is some 250 miles north of Los Angeles, has faced dangerous blizzard conditions since Tuesday, when an atmospheric river-fueled weather system began dumping snow over the Sierra.

Since Tuesday, the area has received 8 to 9 feet of snow, according to the National Weather Service. The resort said the storm total was 94 to 107 inches since Tuesday.

Between blizzard and whiteout conditions, the majority of the mountain’s operations were halted for much of the week, with few lifts and trails open. Even on Friday, with the storm letting up and the weather improving, less than half of the resort’s lifts were operational and only 31 trails were open.

But ahead of an anticipated busy weekend — passes were already sold out for Saturday — resort officials were warning skiers and snowboarders that the threat resulting from the storm will likely linger.

“Conditions are currently dangerous,” a post on Mammoth’s Facebook page read. “Snow Immersion Suffocation (SIS) danger will remain a threat through the weekend – ski and ride with a buddy and keep your buddy in sight at all times.”

Snow immersion suffocation incidents are very rare, with data from the 2016-2017 season showing six fatal cases, and 41 total in the 10 years prior, according to the National Ski Areas Association.