Los Angeles, California - Eight of the nine skiers who went missing in California after an avalanche have been found dead, and one remains missing in horrific blizzard conditions, police said Wednesday.

Rescuers have been desperately searching for the group, which was caught in the avalanche early Tuesday on Castle Peak in the Tahoe area. Earlier, six skiers were found alive, two of them being taken to the hospital.

"We are still looking for one of the members at this time," Nevada County Sheriff Shannan Moon said, cautioning that the storm is hampering any movement.

"Extreme weather conditions I would say is an understatement: lots of snow, gale-force winds, winds making it impossible to see," Moon said.

Blackbird Mountain Guides, the company leading the doomed backcountry trip, said the 11 clients and four guides had been staying at the Frog Lake huts since Sunday and were "in the process of returning" back to base.

Over 40 first responders launched the search, according to officials, including "highly skilled rescue ski teams" from both Boreal Mountain Ski Resort and Tahoe Donner's Alder Creek Adventure Center.

But after quickly finding the six known survivors, the teams came up empty-handed.

Experts had warned of severe avalanche risk.

Placer County Sheriff Wayne Woo pleaded with the public to stay away until the weather clears: "Please avoid the Sierras during this current storm and in the upcoming days, avoid mountain travel. It's treacherous."

California Governor Gavin Newsom has been briefed on the operation.