A huge avalanche swept through Castle Peak in California's Tahoe area on Tuesday, leaving nine backcountry skiers missing. The group of 15 skiers was caught in the avalanche amid a heavy snowstorm. Rescue teams worked through fading daylight and harsh weather to find survivors. Six skiers were rescued with injuries; two were sent to the hospital. The Nevada County Sheriff’s Office said it took several hours to reach the skiers safely. "Due to extreme weather conditions, it took several hours for rescue personnel to safely reach the skiers and transport them to safety where they were medically evaluated by Truckee Fire," the sheriff’s office stated. The number of people on the trip was corrected from 16 to 15. If the missing skiers perish, this could be one of the deadliest avalanches in US history.