The toll in the flash flood in Sikkim mounted to 21 on Friday as Army and NDRF teams worked their way through slushy earth and fast flowing water in the Teesta river basin and downstream north Bengal for the third day in search of those who were swept away and are still missing, officials said.

Of the 23 army personnel who were missing from Burdang area, the bodies of seven have been recovered from different areas downstream while one was rescued and the search is on for 15 missing jawans, Chief Minister P S Tamang said.

A total of 103 people, including the 15 jawans, remained missing after a cloudburst over Lhonak Lake in North Sikkim in the early hours of Wednesday triggered the flash flood.

So far, 2,411 people have been evacuated and accommodated at relief camps, while the calamity has affected over 22,000 people, the Sikkim State Disaster Management Authority (SSDMA) said in its latest bulletin.

The flash flood in the Teesta River, triggered by the cloudburst in Lhonak Lake, caused accumulation of huge quantity of water, which turned towards Chungthang Dam destroying the power infrastructure before moving downstream in spate, flooding towns and villages.

The flood destroyed 13 bridges in the state, with eight bridges getting washed away in Mangan district alone. Three bridges were destroyed in Gangtok and two in Namchi.

Of the civilian deaths, six were reported in Gangtok, and four each in Mangan and Pakyong.

A total of 103 people were missing after the incident. Of them, 59 people were reported missing in Pakyong, 22 in Gangtok, 17 in Mangan and five in Namchi.

Chungthang town bore the maximum brunt of the flood with 80 per cent of it getting severely affected. The NH-10, considered the lifeline of the state, sustained extensive damage at several places.

Meanwhile, the search for the remaining 15 missing army personnel is underway downstream near Teesta barrage.

At the site of the incident in Burdang, army vehicles have been dug out and stores were recovered, a defence release said, adding tracker dogs and special radars have been deployed in the search operations.

It said that the army has been able to take account of 1,471 tourists stranded in Lachen, Laching and Chungthang areas.

With the weather improving on Friday, there may be a window of opportunity for evacuation of the stranded tourists by helicopters, it said.

Surveys are being carried out by all agencies to assess the damage and plan restoration of road connectivity. The road link between Singtam and Burdang has been restored with the clearing of a single lane for vehicular traffic, the release said.

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