KATHMANDU — The humanitarian catastrophe gripping Nepal escalated rapidly today as disaster relief officials doubled the estimated tally of missing persons to nearly 1,900 following devastating flash floods.

The sharp surge in figures follows reports that approximately 900 workers disappeared from several critical hydropower projects submerged by torrents of mud and debris.

Emergency responders are battling treacherous terrain, though rescue operations remain severely hampered by mounting fears of imminent secondary flooding across devastated valleys.