A 64-year-old woman believed to have died in Nepal's devastating floods was found alive Saturday after spending 10 days trapped inside the remains of her home, surviving in a narrow pocket of air beneath water, mud and debris.

Chandrika Shrestha was rescued from her collapsed four-story house in Betrawati, one of the areas hardest hit by the disaster, after police officers heard a faint voice calling for help.

"The four-storey house was swept away by the floods and was left in the middle of quicksand. While walking around it, we heard a voice, 'Save me,'" police officer Mahendra Darnal said.

Darnal and his team spent about 45 minutes reaching Shrestha, who was trapped in a confined space inside the mud-covered structure. She was taken to an army hospital for treatment.

The rescue came after her family had already begun mourning her death.

"I was in touch with the family and they had started the 11-day mourning period," Darnal said.

Shrestha's survival offered a rare moment of hope as rescuers continued searching for thousands of people missing after a catastrophic wall of water and debris tore through Nepal's mountainous districts on Aug. 26.

The disaster, triggered by a glacial and mountain collapse along the China-Nepal border, destroyed homes, roads, bridges and other infrastructure and buried entire communities under thick layers of mud and debris.

Nepali authorities said Sunday that 1,342 bodies had been recovered in the country, while about 4,996 people remained missing.

The disaster agency's figures, combined with casualties reported in China's Tibet Autonomous Region, put the overall death toll at 1,385, with more than 5,500 people still unaccounted for.

Rescuers search for signs of life

Betrawati has become one of the main centers of the search. Much of its market and residential area has been buried under deposits that have hardened almost like concrete, leaving rescuers to dig through collapsed buildings with shovels and search for pockets where survivors might still be trapped.

Workers wearing hard hats have crawled through gaps in the rubble, periodically blowing whistles in the hope of hearing a response.

Five days before Shrestha's rescue, 24 badly decomposed bodies were recovered from a building in Betrawati's market area that had housed a small shop, Darnal said.

Despite the scale of the destruction, rescuers have continued to find survivors.

Two Nepali hydropower workers were pulled alive from the Trishuli 3A tunnel a day before Shrestha was rescued. A Chinese man was also found alive Saturday inside another hydropower tunnel near the Trishuli River.

Three of the recent survivors were found inside hydropower tunnels, where authorities had initially believed more than 100 workers could still be alive.

"Search and rescue is going on at the tunnels despite geography, adverse weather and lack of connectivity," Energy Minister Biraj Bhakta Shrestha told Agence France-Presse (AFP).

At least 12 hydropower projects were affected by the disaster, further complicating efforts to reach people believed to be trapped underground.

Authorities estimate that more than 900 people could be trapped in the area around the Trishuli River.

Other extraordinary stories of survival have emerged from the disaster. An 8-year-old boy was rescued and reunited with his mother, while school principal Rajendra Dawadi quickly ordered an evacuation as the floodwaters approached, helping save hundreds of students.

"If the information was wrong, we would lose a day of schooling," Dawadi told AFP. "But if it was true, we were going to lose our lives."

Thousands remain missing

As search operations entered their 12th day Sunday, hopes of finding more survivors were beginning to fade, but rescue teams continued working through mud, collapsed structures and tunnels.

Hundreds of bodies have been swept down rivers and recovered far from the worst-hit Rasuwa district. In Chitwan, hundreds of miles away, authorities have conducted mass burials for unidentified bodies that had become badly decomposed.

Police have taken DNA samples from the bodies before burial in the hope that they can eventually be matched with relatives. Only about 100 bodies have so far been identified and returned to their families.

Nepal is scheduled to observe a national day of mourning Monday, the 13th day after the disaster, in accordance with a traditional Hindu mourning period.

The United Nations has warned that the scale of the destruction has made the delivery of aid extremely difficult and launched a $50 million appeal to assist more than 84,000 people affected by the disaster.

U.N. Resident Coordinator Lila Pieters Yahia described the speed of the catastrophe as devastating.

"You lose your home, you lose your livelihood, you lose your loved one and you lose the breadwinner of your family," she told AFP in Kathmandu on Sunday, describing how people's lives were transformed within "one to two minutes."

Foreign Minister Shisir Khanal has called the disaster a "Himalayan tsunami" and warned that rebuilding could cost billions of dollars.

Energy officials are also working to restore electricity to isolated communities, including through solar power in areas that remain inaccessible.

A disaster with wider consequences

The disaster also caused significant loss of life in China's Tibet Autonomous Region. China's state news agency Xinhua reported Sunday that the death toll there had risen to 43, with another 519 people missing.

Foreign journalists are not permitted to travel freely in Tibet and generally can visit only on tightly controlled trips organized by Chinese authorities. Chinese state media have focused largely on rescue operations and the scale of the disaster.

The exact cause of the glacial collapse remains unclear. Scientists have warned, however, that rising temperatures are accelerating the melting of glaciers worldwide and increasing the risk of floods and other disasters in vulnerable mountain regions.

For rescuers in Nepal, the search continues despite the worsening odds.

In Betrawati, Shrestha's rescue has become a powerful reminder that beneath the hardened mud and shattered buildings, there may still be people waiting to be found.

Prime Minister Balendra Shah said her survival had "given hope to the entire nation."