Army helicopters ferry survivors from inaccessible areas to a camp at a barracks in Bidur

The three women sat together in the army tent and wept. They cried out for their sons, their husbands, their homes. As flash floods coursed through the Himalayan mountains on Wednesday morning, a monstrous black wave took everything from them.

As a melting glacier high up in the Himalayas between Tibet and Nepal splintered and crashed into the valley below, it set off a deadly cascade of water, mud and debris down the Bhote Koshi River. The impact of the glacier collapse was so strong that experts initially reported it as an earthquake. The Nepali village homes that lined the riverbank and clung to the mountainside stood little chance.

South Asia correspondent Hannah Ellis‑Petersen is on the ground in Bidur, one of the most devastated towns in Nepal, after the deadly flash floods that struck on Wednesday morning. Most homes were completely washed away when a tide of mud, rocks and debris flooded the river valley. Those who survived describe clinging on to buildings and trees as the water rushed over them