BEIJING, Aug 29 (Reuters) - The threat of a lake formed after a glacier collapse bursting near the China-Nepal border where a devastating flood occurred earlier this week has decreased, Chinese authorities said on Saturday,

It has probably been the worst 24 hours of my life,” Dr. Radhika Sharma, the daughter of one missing American couple, said.

Shreya Ahuja is searching for her parents after devastating floods struck Nepal. She is calling for international help and communications access as her family waits for news.

Nepal's National Disaster Risk Reduction and Management Authority raised the number of missing to 1,924. It also said nearly 800 people had been rescued.

The Nepali police warned people to head for safety because more water could soak flood-ravaged villages. China said that the risk of a Tibetan lake overflowing had “gradually decreased.” Anupreeta Das Binod Ghimire Mujib Mashal Lily Kuo and Qasim Nauman Fears of more flooding on Friday clouded the desperate search for survivors of the Himalayan deluge,

Anil Goel sent his family in the U.S. a photo of his tour group at the Nepal-Tibet border just before the area was hit by a wall of mud and water.

Many of the Americans still missing since Wednesday, officials and relatives said, were on a trek to Mount Kailash, which is in Tibet and revered by Hindus and Buddhists.

A geologist reflects on the disaster and explains why rapid warming will make deadly glacial floods far more common.