More than 3,000 tourists are stranded in Lachen and Lachung in Mangan district of Sikkim after flash flood hit the area and cut off all road communications are safe on Saturday, officials said.

The Indian Air Force made multiple attempts to carry out rescue and relief operations by Mi-17 helicopters but was unable to fly from Bagdogra as well as Chaten due to the inclement weather, low-lying cloud cover and low visibility conditions in the Lachen and Lachung valley, they said.

The roads to Lachen and Lachung are damaged. An alternative route to Chungthang via Dzongu is in the process of being opened for the rescue teams to move forward.

Teesta Urja has also provided a chopper for the rescue of tourists and the supply of essential commodities to the Chungtang area.

An ITBP team that reached the area is carrying out relief and rescue in Chungthang at the moment, officials said.

The India Meteorological Department in a weather forecast with respect to Mangan district said light to moderate rain is likely to occur at most places in the district over the next five days.

The IMD has also forecasted generally cloudy to overcast sky in Lachen and Lachung for the next five days.

NDRF teams here along with state agencies are busy with rescue operations in areas such as Singtam, Bardang and Rangpo. However, rescue teams have not been able to reach the upper reaches of North Sikkim, Chungthang, Lachen and Lachung.

However, small teams of state agencies with senior government officers have trekked from Mangan to Chungthang and are accessing the damage and providing much-needed information to the state government.

More rescue teams like the India Reserve Battalion personnel from Mangan are on their way to Chungthang on Saturday.

Chungthang bore the brunt of the flash flood in Teesta river. Rescue teams that have already reached Chungthang have informed that almost 80 per cent of Chungthang town has suffered damage in flash flood.

A cloudburst over Lhonak Lake in North Sikkim in the early hours of Wednesday triggered the flash flood in the Teesta river in which 27 people including eight Army men were killed and 141 people missing.

More than 1,200 houses were damaged in the flash flood which also washed away 13 bridges in the picturesque Himalayan state.

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