An environmental think tank says rescue teams in Nepal are at risk of flash floods up to 18 metres high as a result of unstable glacier-fed lakes.
Nouveau Eco, which studies the economic impact of climate change, said the natural dams holding the lakes back were weak and vulnerable to landslides, as well as aftershocks following the deadly earthquake which devastated the country.
Chief executive Belinda Storey said some Nepalese villagers knew of the risks, but many aid workers did not. Some will be heading into rural areas on rescue missions, unaware of the danger.
Ms Storey said more than 10,000 people lived directly in the path of the three highest risk glacial lakes.