The search for a hiking group that disappeared in an avalanche last week was called off Monday amid dangerous conditions in an area of the Himalayas where officials say they have had to rescue about 200 people.

Seven remained missing after last week’s crush on a trail around Annapurna, where tourists flock to see the world’s 10th-highest peak. Military and government officials have joined tourism groups, locals and others to look for the four South Korean hikers and their three Nepali guides, and to bring scores of others “whose lives were in jeopardy” to safety, Nepal’s tourism department said in a statement.

But avalanches and heavy snowfall have thwarted those operations, the department said. Poor conditions kept a military helicopter with rescue teams from landing Monday, Reuters reported.

“It is a big disaster, and the government is concerned about the safety of tourists,” Mira Acharya, director of Nepal’s tourism department, told Reuters. “Rescuers are on standby for a fresh search.”

About 140 foreign hikers were among the tourists, guides and others rescued during the weekend, Reuters said, citing police. Nepal law enforcement and tourism officials did not immediately respond to inquiries from The Washington Post.

Officials said the still-missing travelers were caught Friday morning when an avalanche sparked by heavy snowfall slammed trails on the Annapurna Circuit trek, on which tourism companies advertise multiweek journeys through stunning scenery. Annapurna rises nearly 27,000 feet, but the circuit trek maxes out at the Thorung La pass, below 20,000 feet.

All trekkers in the area besides the group of seven have been flown to safety, Acharya told the Associated Press. Authorities described the South Koreans still missing as two women and two men, all teachers, who were in Nepal to volunteer, according to South Korean news media.

The Korean ambassador to Nepal and families of those trapped in the avalanche have been involved in search-and-rescue work, officials said.

Um Hong-gil, a South Korean climber helping to look for those missing, told South Korea’s Yonhap News Agency on Monday that he feared a “prolonged” search.

“A person who went close to the scene told me that a huge chunk of ice that had been piled up on high grounds for a long time collapsed along with the snow,” he said to the news organization. “This snow and ice has poured down into a deep valley and likely won’t melt well even when the spring comes.”

Weather and continued avalanches also interfered Sunday with search efforts of the Trekking Agencies’ Association of Nepal, according to Reuters, and a representative from a rescue company told Reuters that a helicopter was not able to determine where the South Koreans and their guides disappeared.

Mountaineering has long been “the major tourism activity” in Nepal, generating significant revenue since the country’s peaks opened to climbers in 1949, officials say. But it can be dangerous. A snowstorm that hit Annapurna during peak trekking season in fall 2014 killed dozens and forced the rescue of hundreds more.

More recently, in 2018, five South Korean climbers and their four guides died elsewhere in the Himalayas when a block of ice crashed down into a gorge, according to Reuters. That was the worst accident of its kind since 18 climbers died in an avalanche on Mount Everest three years earlier.

Abha Bhattarai contributed to this report.

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