The men have been stuck in the 4.5-km (3-mile) tunnel in Uttarakhand state since it caved in early on Nov. 12 and are safe, authorities have said, with access to light, oxygen, food, water and medicines.

Authorities have not said what caused the tunnel collapse, but the region is prone to landslides, earthquakes and floods. Efforts to bring the men out have been slowed by snags in drilling in the mountainous terrain.

By Wednesday, rescuers drilled through 42 m (130 ft) of an estimated 60 m (197 ft) that need to be cleared in order to push through a pipe wide enough for the men to crawl out, said Mahmood Ahmed, an official of the firm building the tunnel.

“Many hurdles can emerge, but if they don’t, we hope that by late in the night or early tomorrow we all will get some good news,” Ahmed, the managing director of the National Highways and Infrastructure Development Corporation (NHIDCL), told reporters.

Possible obstructions in the debris could include large boulders, stones and metal girders, he said, adding that welding together the evacuation pipe needed more time than drilling.

First images from within the tunnel showed workers in white and yellow hardhats standing in the confined space and communicating with rescuers on Tuesday, after a medical endoscopy camera was pushed through a smaller pipeline.

The trapped men have been receiving fruits and cooked food items after a second, larger pipeline was pushed through on Monday.

Toiletries and clothing have also been pushed through, said

Neeraj Khairwal, a rescue co-ordination official.

“The workers are very positive and they are in a very good mental state,” he added.

Physicians and chest specialists are among 15 doctors at the site, said R.C.S. Panwar, the district’s chief medical officer, with 40 ambulances set to be placed on standby.

The anxious families of 11 of the 41 trapped men have reached the accident site, eager to see them rescued. Those trapped are low-wage workers, most of them from poor states in India’s north and east.

“I am worried, and will be worried, while my brother is not out of this tunnel, but now it looks like the time has come,” said Indrajeet Kumar, who travelled from the eastern state of Jharkhand, worried about his trapped brother, Vishwajeet.

The floods triggered by torrential rain and overflow from the Lhonak Lake were among the region’s worst in more than 50 years, washing away homes and bridges in the northeastern state of Sikkim, wedged between Bhutan, China and Nepal.

The state government has begun the process for such a designation of those still missing, by seeking the federal government’s permission, since the law specifies an interval of seven years before a missing person can be declared dead.

“We have not called off the rescue efforts, but after two weeks it will be a miracle (to find them),” said state official Anil Rai.

Sikkim retrieved at least 40 bodies in the flood aftermath and the neighbouring state of West Bengal 60, said officials from the two states who are working to reconcile the official toll and eliminate double counting.

As climate change warms high mountain regions, many communities face the risk of dangerous glacial lake outburst floods (GLOFs).

Lakes holding water from melted glaciers can brim over and burst, sending torrents rushing down mountain valleys.

More than 200 such lakes now pose a high hazard to Himalayan communities in Bhutan, China, India, Nepal and Pakistan, research in 2022 showed.

Following days of torrential rain in the northeastern state of Sikkim, torrents of water swept down narrow river valleys from Lohnak Lake, damaging a dam and wreaking destruction in villages and Rangpo town, about 50 km (30 miles) south of state capital Gangtok.

Sikkim’s Chief Secretary Vijay Bhushan Pathak, the most senior bureaucrat, told Reuters that rescuers had found 25 bodies in the state and bodies of eight army men washed away were found in the neighbouring downstream state of West Bengal.

He said 101 people were still missing in the latest of a series of natural disasters caused by extreme weather events in the Himalayas. Fourteen army personnel were among the missing, a defence ministry statement said.

The search for survivors was hampered by damaged roads, poor communications and bad weather, and residents were struggling to clear sludge and debris in the wake of one of the worst disasters in the remote region in more than 50 years.

Parveen Shama, the top district official of Jalpaiguri in West Bengal, said 41 bodies were found in the district.

A statement from the federal government said chief secretary Pathak told a meeting of the National Crisis Management Committee that road connectivity has been established in most areas, 28 relief camps established and more than 6,800 people given shelter there.

“As a result of improvement in weather conditions, it has become possible to start evacuation and air lifting of stranded people. Eighty people have been evacuated this morning,” the statement quoted Pathak as saying.

Priority To Connectivity, Evacuation

Federal cabinet secretary Rajiv Gauba said portable bridges known as Bailey bridges should be launched on priority to restore road connectivity for people where bridges have been washed away, the statement said.

“Evacuation of people in shortest possible time should be the priority,” Gauba said.

Sikkim, a Buddhist state of 650,000 people wedged in the mountains between Nepal, Bhutan and China, received 101 mm (four inches) of rain in the first five days of October, more than double normal levels.

In October 1968, an estimated 1,000 people in Sikkim perished in floods.

Mukesh Kumar, a 43-year-old migrant worker in Rangpo, described how he and his neighbours had barely 10 minutes to escape before the flash flood hit.

“Had we not left for another two minutes, we might have drowned,” said Kumar, staring at the sludge and debris covering his lodgings.

Residents told Reuters that many people whose dwellings were on the ground floor could not have survived.

Baiju Sharma, 45, who ran a furniture business, surveyed the aftermath of the disaster.

“Where you are standing is 15 feet (4.5 metres) higher than earlier. You are standing on his house,” Sharma said, pointing towards his neighbour.

Government officials said about 2,000 tourists stuck in cut off areas of northern Sikkim were reported to be safe, and state authorities and the army had provided them with food and communication facilities to contact their families.

At least 18 people have died and nearly 100 remain missing as heavy rains and water gushing out of Lhonak Lake unleashed flash floods on Wednesday in the Teesta river in Sikkim state, which borders Nepal, Bhutan and China.

It is the latest in a series of extreme weather events that have caused widespread damage in the Himalayas of South Asia in recent years and have been blamed by scientists and officials on climate change.

What Caused The Flooding?

The primary reason for the destruction in Sikkim was excess rainfall and a glacial lake outburst flood (GLOF) in Lhonak Lake at an altitude of 5,200 metres (17,060 ft), India’s National Disaster Management Authority said.

Glacial lakes are formed when a glacier melts and fills the depression left behind. There are 503 glacial lakes in the Indian Himalayas that are larger than 10 hectares – close to the size of 10 rugby fields put together, according to a 2011 assessment by India’s Central Water Commission.

Satellite images released by India’s space agency on Thursday showed that Lhonak Lake more than halved in size after it flooded.

The images also show a lot of ice floating on the lake surface, said Jakob F. Steiner, a fellow at the Kathmandu-based International Centre for Integrated Mountain Development (ICIMOD), part of the Himalayan University Consortium.

“On the south of the Lhonak Lake there are steep slopes, glaciers as well, there is still snow. It could be that a chunk of either ice or unstable slopes has detached and dropped into the lake water,” Steiner said, adding that the images indicate something like this happened.

This can create shockwaves across the water surface that would be enough to topple the lake’s dam, Steiner added, since the lake is up to 120 metres (395 ft) deep.

Finu Shrestha, a remote sensing and geo-information analyst at ICIMOD, said a combination of factors including rainfall, a snow avalanche and increasing pressure on the lake due to its growing size could have caused it to flood.

Sharad Chandra, director of the flood forecasting division at India’s Central Water Commission, said two earthquakes that struck Nepal on Tuesday, of magnitudes 6.3 and 5.3, could also be one of the probable reasons behind the GLOF event.

Were There Warnings And Similar Events In The Past ?

Indian scientists at the National Remote Sensing Centre had said in a 2013 report that there was a 42% chance of Lhonak Lake bursting its banks.

It said the lake had grown in size, from 17.54 hectares (43.34 acres) in 1977 to 98.73 hectares (243.97 acres) in 2008. Latest satellite imagery showed the lake area as approximately 162.7 hectares before it burst and shrank to 60.30 hectares.

Deadly flash floods have previously been triggered multiple times due to GLOF events in the Himalayas, including a 2013 disaster in Kedarnath in Uttarakhand state that killed about 5,000 people.

Floods caused by days of heavy rains in Sikkim in 1968 killed an estimated 1,000 people.

The Lhonak Lake in Sikkim state burst its banks on Wednesday causing major flooding, which authorities said had impacted the lives of 22,000 people. It is the latest deadly weather event in South Asia’s mountains being blamed on climate change.

The weather department said Sikkim received 101 mm (4 inches) of rain in the first five days of October, more than double normal levels, triggering floods worse than one in October 1968 in which an estimated 1,000 people were killed.

The department has predicted heavy rain over the next three days in parts of Sikkim and neighbouring states.

The latest flooding was exacerbated by water released from state-run NHPC’s Teesta V dam, local officials said. Four of the dam’s gates had been washed away and it was not clear why they had not been opened in time, a government source told Reuters.

As of early Thursday, the state disaster management agency said 26 people had been injured and 102 were missing, 22 of whom were army personnel. Eleven bridges had been washed away, hampering rescue operations which were already affected by heavy rainfall.

Authorities in neighbouring Bangladesh were on alert with a state-run water development board official warning that five districts in the northern part of the country could be inundated with a rise in the level of the Teesta river, which enters Bangladesh downstream of Sikkim.

“Continued efforts are on to dig out vehicles submerged under the slush at Burdang near Singtam. The search for the missing persons is now focusing in the areas downstream of Teesta river,” an Indian defence spokesperson said.

Fuel Scarc, Food Available

Video footage from the ANI news agency, in which Reuters has a minority stake, showed flood waters surging into built-up areas where several houses collapsed. Army bases and other facilities were damaged and vehicles submerged.

Satellite imagery showed that nearly two-third of the lake seems to have been drained.

Sikkim, a small state of about 650,000 people which is wedged in the mountains between Nepal, Bhutan and China, was cut off from Siliguri in the neighbouring state of West Bengal as the main highway had collapsed.

State lawmaker G.T. Dhungel told Reuters that petrol and diesel had become scarce in state capital Gangtok but food was readily available.

A cloudburst on Wednesday dropped a huge amount of rain over a short period on the Lhonak Lake, about 150 km (90 miles) north of Gangtok near the border with China, triggering flash floods down the Teesta valley.

A 2020 report by India’s National Disaster Management Agency said glacial lakes are growing and pose a potentially large risk to downstream infrastructure and life as glaciers in the Himalayas are melting due to climate change.

“Sadly, this is the latest in a series of deadly flash floods that ricocheted across the Hindu Kush-Himalayan region this monsoon, bringing the reality of this region’s extreme vulnerability to climate change all too vividly alive,” said Pema Gyamtsho, director-general of the Nepal-based International Centre for Integrated Mountain Development.

Other mountainous areas of India, as well as parts of neighbouring Pakistan and Nepal, have been hit by torrential rains, flooding and landslides in recent months, killing scores of people.

A report by India’s National Remote Sensing Centre scientists a decade ago had warned the chances of the lake bursting its banks was “very high” at 42%.

At least 240 people have died this year in the mountainous region as landslides and flash floods triggered by heavy rains buried homes and destroyed crops and infrastructure.

Seasonal monsoon showers are vital for India’s $3-trillion economy, bringing nearly 70% of the rain the country needs to water farms and refill reservoirs and aquifers.

But the monsoon’s convergence with a low-pressure weather system in the Himalayas in recent years has caused extremely heavy rains, something that scientists and officials have blamed on rising temperatures.

“Think of it as a collision of two forceful systems,” said Kuldeep Srivastava, head of the India Meteorological Department’s regional centre in New Delhi.

“It causes significant rain, or even cloudbursts … we are noticing in the last few years, intense spells of rain lasting short durations,” he said, adding that this was due climate change driven by global increase in temperatures.

The number of very heavy to extremely heavy rainfall days per decade in India’s Himalayan states of Himachal Pradesh (HP) and neighbouring Uttarakhand increased to 118 between 2011 and 2020 from 74 in the preceding decade, data from the weather office showed.

At least 166 people have died in HP and 74 in Uttarakhand this year since June in landslides, flash floods and other rain-related incidents, according to government data.

Rains battered the two states following the convergence of the monsoon system with Western Disturbances, a weather system that originates in the Mediterranean Sea and moves east, bringing moisture-laden winds that cause winter rain and snow in the Himalayas.

Western Disturbances usually pass north of India’s northern border between the summer and monsoon months of June and October, but, as temperatures rise, some of them move slightly south, said V.P. Dimri, director of the Indian Institute of Geomagnetism.

“Because of sea surface temperature warming, the Western Disturbances have more energy … similarly, general warming of the earth is also leading to change in wind motions,” he added.

Monsoon rainfall patterns across India have seen a climatic shift in the recent decades, said Roxy Mathew Koll, a scientist at the Indian Institute of Tropical Meteorology.

Unusually heavy rain and melting glaciers have brought deadly flash floods to the mountains of India and neighbouring Pakistan and Nepal over the past year or two, with government officials increasingly blaming climate change.

Television footage from India’s Himachal Pradesh state showed houses flattened by landslides, buses and cars hanging on the edge of precipices after roads gave way, and hundreds of people at rescue sites as emergency workers struggled to clear debris.

“Again, tragedy has befallen Himachal Pradesh, with continuous rainfall over the past 48 hours,” the state’s chief minister, Sukhvinder Singh Sukhu, said in a post on the messaging platform X, formerly known as Twitter.

More than 50 people had died in rain-related incidents within 24 hours, Sukhu told Indian news agency ANI, in which Reuters has a minority stake.

“This number can rise further because 20 people are still trapped,” he said.

Officials from the state disaster management authority, meanwhile, said that 41 bodies had been recovered by Monday evening.

“Another 13 people are missing but, as time passes, we are losing hope that they will be pulled out alive,” said state disaster management official Praveen Bhardwaj.

In one of the most deadly incidents, a temple collapsed in the state capital, Shimla, with rescuers pulling out at least nine bodies, the chief minister said.

In Solan district, houses collapsed, killing at least seven people, and a mother and her child were killed in Mandi district when their house collapsed, Bhardwaj said.

Television footage showed swollen rivers breaking their banks in Himachal and neighbouring Uttarakhand state, where also two people died and four were missing in incidents related to the rains, the Uttarakhand Disaster Management control room told Reuters.

The India Meteorological Department issued a “red alert” for both states on Monday and has forecast rainfall intensity to reduce from Tuesday onwards.

Parts of Himachal and Uttarakhand received as much as 273 mm (10.75 inches) and 419 mm (16.54 inches) of rain in 24 hours till 8:30 am IST (3 am GMT) on Monday, the weather office said.

Schools and other educational institutes were ordered to close in Himachal Pradesh and people in vulnerable areas were being moved to relief shelters, state officials said.

Uttarakhand state authorities announced that the Char Dham pilgrimage route would be closed until Tuesday following landslides.

Unusually heavy rain and melting glaciers have brought deadly flash floods to the mountains of India and neighbouring Pakistan and Nepal over the past year or two with government officials increasingly blaming climate change.

Television footage from India’s Himachal Pradesh state showed houses flattened by landslide, buses and cars hanging on the edge of precipices after roads gave way, and hundreds of people at rescue sites as emergency workers struggled to clear debris.

“Again, tragedy has befallen Himachal Pradesh, with continuous rainfall over the past 48 hours,” the state’s chief minister, Sukhvinder Singh, said in a post on the messaging platform X, formerly known as Twitter.

“Reports of cloudbursts and landslides have emerged from various parts of the state resulting in loss of precious lives and property.”

Reports of more casualties kept coming in on Monday as the chief minister inspected some of the damage.

In one the most deadly incidents, a temple collapsed in the state capital, Shimla, with rescuers pulling out at least nine bodies, the chief minister said.

Schools and other educational institutes had been ordered to close and people in danger were being moved to safety in shelters, state officials said.

Parts of the state had received as much as 273 mm (10.75 inches) of rain in 24 hours, the India Meteorological Department said.

“This is the first time we’re seeing multiple cloudburst incidents and widespread damage in the state,” said state disaster management official Praveen Bhardwaj.

In the Solan district, houses collapsed after a cloudburst, killing at least seven people, and a mother and her child were killed in the Mandi district when their house collapsed, Bhardwaj said.