Nepal Quake Death Toll Surges to 3,218

"The death toll has reached 3,218 and over 6,500 are injured," said Rameshwor Dangal, who heads the home ministry's national disaster management division.

The toll for Nepal had previously stood at 2,430. Around 90 people are also known to have died in neighbouring countries, including India and China, AFP reported.

Roads leading out of the mountain valley city of one million were jammed with people, many with babies in their arms, trying to climb onto buses or hitch a ride aboard cars and trucks.

Many said they had slept in the open since Saturday's quake, either because their homes were flattened or they were terrified that the aftershocks would bring them crashing down.

"We are escaping," said Krishna Muktari, who runs a small grocery store in Kathmandu city. "How can you live here? I have got children, they can't be rushing out of the house all night."

Overwhelmed authorities were trying to cope with a shortage of drinking water and food, as well as the threat of disease.

The sick and wounded were lying out in the open in Kathmandu, unable to find beds in the devastated city's hospitals. Surgeons set up an operating theatre inside a tent in the grounds of Kathmandu Medical College.

"We are overwhelmed with rescue and assistance requests from all across the country," said Deepak Panda, a member of the country's disaster management.

High in the Himalayas, hundreds of foreign and Nepali climbers remained trapped after a huge avalanche ripped through the Mount Everest base camp, killing 17 people in the single worst disaster to hit the world's highest mountain, Reuters reported.