Desperate families ran their fingers down long lists of rescued people posted outside a military base Saturday, searching for names that could offer hope three days after devastating floods swept through northern Nepal.

The lists stretched across several pages, each name representing someone who survived the tsunami-like surge of freezing water, mud and debris that tore through communities near the Nepal-China border Wednesday morning.

For many families, however, the names they were looking for were missing.

At least 675 people have been killed and 2,426 remain missing in Nepal, authorities said Saturday, as rescue teams continued searching areas buried under mud and rock. The disaster has destroyed roads, submerged settlements and cut off parts of the region, severely complicating rescue efforts.

Chinese state media earlier confirmed seven dead in Tibet following Wednesday's disaster, taking the total killed to 682.

In Bidur, the last major town before the road to China, military personnel have established a hub for rescue operations.

Rishi Shrestha searched the lists for his 35-year-old cousin, Rajan Shrestha, who was traveling north toward Tibet and the Chinese frontier when the floods struck.

Rishi said he spoke to Rajan that morning after he stopped for tea near the border. It was their last conversation.

"It's been more than three days, so 99 percent he is not alive," Shrestha said outside the military base.

He said soldiers told families that rescuers were mostly finding people who had managed to reach higher ground.

"But it seems he was just buried," he said.

The US Geological Survey said the disaster was caused by a glacial collapse that unleashed a massive torrent of water and debris downstream.

Entire settlements were engulfed in mud and rock, while damaged roads and unreliable phone service have made it difficult for families to learn what happened to their relatives.

Kalka Sharda found no sign of his 18-year-old son, Vinod, a laborer at the Upper Trishuli hydropower plant.

"My son's name is not there," he said. "I don't think there is any hope left because if he was alive, he would have found a way to get in touch."

Pasang Sherpa has spent three days outside the military camp waiting for word about her brother, Chiring Tamang, a 40-year-old truck driver who was returning home after crossing from China.

He stopped in the border town of Timure to rest for the night and was likely on the road when the floods struck.

"It is increasingly unlikely he is still alive," Sherpa said. "But at least we should get his dead body for some closure. My parents are at home crying and waiting for their son."

Others continued to cling to even the smallest possibility that their relatives survived.

Dil Tamang's father crossed the China border Wednesday morning to go to the market and never returned. Tamang said he received a message in Chinese containing the names of people believed to have survived.

His father's name appeared on the list, but he had yet to confirm whether the information was genuine.

"If I could just talk once to him..." Tamang said, his voice trailing off.

Billions in reconstruction costs

The scale of the destruction was already forcing Nepal's government to consider a recovery effort that could cost billions of dollars.

Foreign Minister Shisir Khanal said Saturday that reconstruction and rehabilitation could require "billions of dollars" and appealed to the international community for assistance.

"The urgency is on rescue and saving lives as much as we can," Khanal told reporters in Kathmandu.

He said the government would conduct a detailed assessment of the damage but was already struggling with limited resources.

Rescue teams have recovered hundreds of bodies, many of them found downstream after being carried away by the floodwaters. Authorities now face the difficult task of preserving and identifying the remains while families wait for confirmation.

Khanal said Nepal's health system lacks sufficient capacity to keep the bodies refrigerated for extended periods and that the government had asked international partners to provide equipment.

"Hundreds of bodies have been found downstream, and there is a risk of fast decomposition because these bodies have been in water for a long time," he said.

Authorities are considering bringing in refrigerated trucks normally used to transport perishable goods to help preserve the remains.

Identifying the dead presents another major challenge.

"We need forensic capability," Khanal said, adding that Nepal has limited capacity for DNA sampling, testing and reporting.