Aid has begun to reach remote regions near the epicentre of Saturday’s devastating earthquake in Nepal.
As relief efforts continue in the Kathmandu Valley, the UN says the response is broadening to include areas such as Dhading and Gorkha.
The 7.8-magnitude quake killed more than 5,000 people. Many survivors are in desperate need of food and water.
Thousands of people are queuing to board buses and leave the capital, amid fears of further aftershocks.
The government is providing free transport for Kathmandu residents. School buses have been sent to supplement overstretched services.
“We are scared of the epidemics that may spread because of all those dead bodies,” a man waiting at the main bus station told the BBC. “Just to be safe, I’m leaving town for a while.”
Early on Wednesday police at the station scuffled with people trying to get on to crowded buses.
Rescue operations resumed on Wednesday following bad weather.
Bella Messenger, an NGO worker in a remote part of Gorkha district, told the BBC that Chinese lorries had brought aid to the area, but many people remained cut off.
“You can’t get to some villages without a helicopter,” she said. “Some villages you can get to with a two-hour hike.”
Some villages have been almost totally destroyed. There are accounts of desperate residents rushing towards relief helicopters begging to be airlifted.
“We haven’t had any food here since the earthquake,” Sita Gurung, whose home in Gorkha was destroyed, told AFP news agency. “We don’t have anything left here.”
More than eight million people have been affected by the quake, the UN says. About 10,000 people have been injured.
Hundreds of thousands of people continue to live in temporary camps, in squalid conditions with very little food and water, says the BBC’s Sanjoy Majumder in Kathmandu.
Anger and frustration have been mounting, with many people sleeping out in the open for a fourth night.
Officials admit they have been overwhelmed by the scale of the disaster, but highlight the challenges it poses in one of Asia’s poorest countries.
“The government is trying its best to deliver the relief materials,” National Disaster Management chief Rameshwor Dangal told the BBC. “The problem is the level of disaster is very high and it’s spread all over more than 20 districts.”
Renaud Meyer of the UN Development Programme said Kathmandu’s single-runway airport was struggling to accommodate the rush of aid flights, but teams were delivering supplies as quickly as possible.
“We’re trying to skip the usually fairly long moments of assessment to go straight to the delivery of assistance,” he said.
On Mount Everest – where the quake triggered an avalanche that killed at least 18 people – all stranded climbers have now been evacuated from base camp.