The death toll in flash floods in Sikkim jumped to 55 with officials in the Himalayan state confirming 26 bodies were recovered within its territory till Saturday evening while in Bengal, where 27 bodies were fished out of rivers till Friday, two more were found a day later.

Bad weather still hampered rescue and several villages and town neighbourhoods lining the Teesta river as it flowed from Chungthang, in north Sikkim, to Teesta Bazar, at the foothills on the Bengal-Sikkim border, remained under neck-deep layers of silt and debris brought in by the flood.

The first disaster relief personnel reached the Chungthang village in Mangan district, which was the worst hit, late on Friday after trekking for days.

“While the first team of SDRF personnel managed to reach Chungthang on Friday night, a second team reached this [Saturday] morning. Nearly 80% of the town has been damaged and most of the houses, shops and offices are buried under several feet of debris,” a top government official said, asking not to be named.

The SDRF team had to trek for several kilometres through treacherous hilly trails and then cross the Teesta using a precarious suspension bridge to reach the town.

“There are no reports of any casualties from the town till now. Relief has finally reached Chunthang. We hope to restore communication lines within two to three days,” a senior IAS officer posted in Mangan said.

The state administration confirmed it was still counting the mounting losses.

“So far, 26 dead bodies have been found inside Sikkim and 143 people are still missing. As many as 2,565 people have been affected and 1,170 houses were damaged. We have rescued 2,413 people. The state government has set up 22 relief camps,” said Bikash Basnet, press secretary to Sikkim chief minister Prem Singh Tamang.

In West Bengal, where 27 bodies, including those of five Army personnel, were recovered from the Teesta river and its tributaries, two more were found on Saturday. These bodies were found in Darjeeling and Cooch Behar districts — hundreds of kilometres away from North Sikkim.

Union minister of state for the home ministry Ajay Kumar Mishra reached Sikkim on Friday night to take stock of the situation. The MHA in a statement said that Mishra held a meeting on Saturday morning with the chief secretary and head of departments of the state government and other agencies working on the ground.

With bad weather stopping the Sikkim government from deploying helicopters to evacuate stranded tourists from north Sikkim, road engineers started working on an alternative route.

Most of the 3,000 tourists in Sikkim are stranded at Lachen and Lachung, popular destinations in Mangan district.

The floods occurred in the early hours of Wednesday when a glacial lake at south Lhonak burst following torrential rain.

A statement issued by Sikkim’s science and technology department said that on Tuesday a large chunk of moraine got detached from the side wall of the Lhonak lake and fell into the water.

The detached moraine — a clump of loose rocks — plunged into the water, resulting in overflow of huge volumes of water from the lake. As the water pushed its way through the outlet, it widened and deepened the outlake. Huge amounts of water and debris, comprising rocks and boulders, then came crashing through the Goma channel, which joins the Zemu river that, further downstream, joins the Lachen River, a tributary of the Teesta, the statement said.

Bhupendra Chettri, deputy general manager of Sikkim Nationalized Transport, a government of Sikkim undertaking, said in Siliguri that eight buses have been sent to Gangtok to bring back stranded people. Thirty of these people arrived at Siliguri in the evening in one of these buses.

One of the passengers, Meenakshi Choudhary, an engineering student at Sikkim Manipal Institute of Technology (SMIT), said she had to travel for 10 hours. Her relatives, who had come from Dhubri in Assam, were waiting to take her home.

She said: “Many houses near our institute were washed away and the situation in Sikkim is really painful.”

All educational institutes in Sikkim would remain closed till October 15, the state has declared.