Rescuers in Nepal are continuing their search for survivors of the magnitude 7.8 quake that killed thousands.
Overnight tremors had forced residents to spend the night trying to sleep out on the streets and open ground in makeshift tents.
Hospitals in the Kathmandu Valley, the quake-affected region with 2.5 million people, were overcrowded, running out of emergency supplies and space to store corpses, the UN said in a statement.
Most areas are without power and water, but with Kathmandu airport reopening, rescue flights began arriving. Workers are sending out tents and relief goods in lorries and helicopters.
The quake destroyed expanses of the oldest neighbourhoods of Kathmandu, and was strong enough to be felt all across parts of India, Bangladesh, China's region of Tibet and Pakistan.