Dramatic footage captured by Tashi-Lakpa Sherpa showed the large avalanche rolling down the 8,163-meter Himalayan peak and hitting a desperately exposed base camp.
No deaths or injuries have been confirmed.
Mountaineers, Sherpas and workers are seen jostling for safety in the footage, and voices can be heard frantically urging people to “come in”.
Tashi told 9news.com.au via message that the avalanche hit at 9.37am today (local time).
Writing in an Instagram post, Tashi said the avalanche destroyed around six camps and more than 30 tents.
Manaslu, considered the fifth most dangerous mountain in the world, was recently hit by heavy snowfall, he wrote.
Last week, an avalanche that struck above Camp III killed a guide and injured 13 climbers heading to the summit.
Manaslu also suffered another victim last week.
Nelson fell on the vertical side of the summit, he said, while estimating it could have been a 3,000 meter free fall.
Rescuers searching by helicopter located Nelson’s body on Wednesday after failing to find her on Tuesday and Monday when bad weather hampered their search.
Hundreds of local climbers and Sherpas attempt to reach the summit during Nepal’s autumn climbing season.
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