Nepali sleep in provisional tents and under plastic sheets after Saturday's earthquake, near the airport of Kathmandu, Nepal April 28, 2015.[Photo/Agencies]

KATHMANDU - The death toll from Nepal's devastating earthquake could reach 10,000, the prime minister said on Tuesday, as residents frustrated by the government's slow response used their bare hands to dig for signs of their loved ones.

"The government is doing all it can for rescue and relief on a war footing," Prime Minister Sushil Koirala told Reuters. "It is a challenge and a very difficult hour for Nepal."

International aid has finally begun arriving in the Himalayan nation of 28 million people, three days after Saturday's 7.9 magnitude quake, but disbursement is slow. According to the home (interior) ministry, the confirmed death toll stands at 4,349, with over 7,000 injured.

Koirala did not say on what he was estimating the leap in the death toll, but the government has said it is still to establish contact with some remote regions.

"The death toll could go up to 10,000 because information from remote villages hit by the earthquake is yet to come in," he said.

The United Nations said 8 million people were affected by the quake and that 1.4 million people were in need of food.

Nepal's most deadly quake in 81 years also triggered a huge avalanche on Mount Qomolangma that killed at least 17 climbers and guides, including four foreigners, the worst single disaster on the world's highest peak.

All of the climbers who had been stranded at camps high up Qomolangma had been flown by helicopters to safety, mountaineers reported on Tuesday.