TRUCKEE, California, Feb 18 (Reuters) - Eight backcountry skiers were confirmed killed and a ninth was presumed to have perished when their tour group was overtaken by a football-field-sized avalanche in California's Sierra Nevada mountains on Tuesday, in the deadliest U.S. avalanche in 45 years, authorities said.
Six survivors were rescued after search teams on skis fought through blinding snow, darkness, treacherous terrain and gale-force winds to reach them in the rugged Castle Peak area near Truckee, California, about 10 miles (16 km) northwest of Lake Tahoe.
