Sikkim tunnel disaster: Trapped workers count rises from 17 to 25 after methane blast-triggered landslide

A major rescue operation is underway in Sikkim after a methane gas explosion triggered a landslide inside the under-construction NHPC Teesta Stage-VI hydropower tunnel, trapping at least 25 workers deep inside the project site.

According to preliminary reports, methane gas had accumulated in a section of the tunnel located nearly 1.5 kilometres from the entrance. Around midday, an attempt to release the trapped gas reportedly triggered an explosion, which caused a landslide inside the tunnel, cutting off the exit route and trapping the workers.

Some workers managed to escape on their own immediately after the incident. However, several others remain trapped inside the tunnel, including reportedly one worker from Jholungay in South Sikkim's Samardung area.

Providing an update on the rescue operation, Namchi Deputy Commissioner Anupa Tamling said the number of trapped workers has now been revised to at least 25, up from the earlier estimate of 17.

"The figure has been revised based on preliminary verification. The number may still change as authorities continue cross-checking details with company officials and verifying the attendance records of workers present at the site," Tamling said.

The rescue operation has been hampered by extremely hazardous conditions inside the tunnel. Initial attempts by personnel from the Rangpo Fire and Emergency Services had to be abandoned due to dangerously low oxygen levels and the presence of methane fumes, with some rescuers reportedly falling ill during the operation.

Subsequently, teams from the National Disaster Response Force (NDRF) also attempted to enter the tunnel but were unable to proceed because of the high concentration of gas and unstable conditions created by the landslide.

Senior officials from the district administration, NHPC, police and disaster response agencies are stationed at the site and are closely monitoring the situation. Efforts are underway to improve ventilation inside the tunnel and assess the safest method to reach the trapped workers.

As of the latest update, no trapped worker has been rescued, and the operation remains in progress under challenging conditions.

Authorities are continuing to verify the exact number of workers inside the tunnel while rescue teams work against time to reach those trapped beneath the debris.