Nepali troops on Saturday searched rugged snow-covered Himalayan terrain in their most intensive effort to find any remaining survivors of a blizzard that killed 30 people and injured 175 in one of the country's worst mountain disasters.

More than 40 people are still missing after unseasonal weather in peak trekking season unleashed avalanches on the 240-km route around Annapurna, the world's 10th-tallest peak, which takes enthusiasts three weeks to finish.

Twelve helicopters were pressed into action to drop searchers in otherwise inaccessible spots, while soldiers fanned out in different directions.