Sikkim disaster: 12 casualities so far, detailed investigation to be undertaken to ascertain cause, says NHPC

By  News On Air   Jul 21, 2026

At least 12 casualties have been reported so far after a section of the under-construction Head Race Tunnel (HRT) of the National Hydroelectric Power Corporation Limited Teesta Stage-VI Hydroelectric Project collapsed yesterday at Samardung in Namchi district in Sikkim.

NHPC has said that a detailed investigation will be undertaken to ascertain the cause of the incident. Talking to Akashvani News, a senior official from Information and Public Relations Department in Sikkim said that that 25 personnel were trapped inside the tunnel, out of which 12 casualties have been reported so far. 

NHPC informed that the Project Team is working in close coordination with the district administration, National Disaster Response Force, State Disaster Response Force, local authorities and other emergency agencies to support the ongoing rescue operations. In addition to this, a special rescue team from the DG Mines-Safety has also reached the site for rescue operations at the incident site.

According to NHPC, the incident occurred at 1:04 PM yesterday, inside the under-construction Head Race Tunnel (HRT), after the sudden burst of suspected methane gas trapped or embedded inside the rocks. NHPC noted that this led to an explosion generating dense fumes and toxic gases. The Corporation said that the project team activated its emergency response protocols immediately.

NHPC informed that their top Management has reached the site and is closely coordinating with the rescue teams and local authorities. It added that the site engineering teams are working round-the-clock alongside the authorities to assist in stabilizing the tunnel environment and ensuring rescue. It also assured that all possible efforts are being made for evacuation of the trapped personnel.