The death toll due to the flash flood which hit Sikkim has touched 19 with more than 100 others still missing, officials said.

The deceased include six Indian Army soldiers.

The authorities are on alert as the Shako Cho glacial lake near Lachen in Mangan district shows signs of bursting which could result in further tragedy.

Meanwhile, the search operation to locate missing people is going on.

According to the Guwahati-based Defence PRO, the Indian Army is providing assistance in terms of food, and medical aid and extending communication facilities to civilians and tourists stranded in North Sikkim.

"The search for the missing Indian Army soldiers continues with the search focussing in the downstream areas of Teesta Barrage. At the site of the incident at Burdang near Singtam, the army vehicles are being dug out and stores are being recovered. Additional resources in terms of teams of TMR (Tiranga Mountain Rescue), tracker dogs, and special radars have been brought in, to assist in the search operations," the Defence PRO told IBNS.

Meanwhile, Troops of Tri Shakti Corps Indian Army have been able to take account of 1471 tourists present the areas of Lachen/Chatten, Lachung and Chungthang. With the weather improving on 6 Oct, there may be a window of opportunity for evacuation of stranded tourists by  Helicopters.

The same is being planned jointly by the State Government, Indian Army and Indian Air Force.

Survey is being carried out by all agencies to assess the damage and plan restoration of road connectivity.

Sikkim's glacial lake outburst was previously predicted:

Fifteen million people around the world, including 3 million in India, are at risk from flooding caused by glacial lakes, with just four countries accounting for more than half of those exposed, a study had predicted earlier.

An international team of scientists led by Newcastle University had produced the first global assessment of areas at greatest risk of Glacial Lake Outburst Floods and identified priority areas for mitigation.

The research team looked at 1,089 glacial lake basins worldwide and the number of people living within 50 kilometres of them, as well as the level of development in those areas and other societal indicators as markers of vulnerability to GLOFs. They then used this information to quantify and rank the potential for damage from GLOFs at a global scale and assess communities’ ability to respond effectively to a flood. 

The results highlighted that 15 million people live within 50 km of a glacial lake and that High Mountain Asia (which encompasses the Tibetan Plateau, from Kyrgyzstan to China), has the highest GLOF danger, with 9.3 million people potentially at risk. India and Pakistan have around 5 million exposed people – about one third of the global total combined.

The research, which was published in Nature Communications, also highlighted Peru as one of the four countries, along with India, Pakistan and China, that account for more than half of the number of people worldwide exposed to potential danger from glacial lake flooding.

What is GLOFs?

Glacial lake outburst floods (GLOFs) occur when melting glacier-formed lakes burst open due to excessive water accumulation or triggers like earthquakes, causing destructive flash floods downstream.