As a result of the disaster, more than 100 people are still missing and 26 were injured.
Authorities said that the Mangan district was the most affected, as waters swept away 100 houses, buildings and the Tessta-II hydropower plant, and the towns of Chungthang and Lachung remain cut off.
The Sikkim Disaster Management Department said Chungthang was the worst affected with damage to 80 percent of its territory and was cut off from the rest of the state by the blocking of nearby roads and the cutting of communication lines.
According to local media, State Chief Secretary VB Pathak called on everyone to collaborate at a meeting with representatives of the Chamber of Commerce, wholesale retailers, the Pharmacies Association, representatives of the IOC, LPG traders and distributors, gasoline pump owners and the Taxi Drivers Association.
At the time, priority is to transport stranded people by helicopter, especially the elderly and the sick with medical emergencies, an official said.