A major rescue operation continued through Tuesday morning at the under-construction Samardung tunnel of the NHPC Teesta Stage VI Hydroelectric Project in Sikkim's Namchi district, with authorities confirming that seven people have lost their lives in the incident.
According to the latest official update, the bodies of the deceased have been shifted to Singtam District Hospital, STNM Hospital in Gangtok and Namchi District Hospital.
Search and rescue teams are continuing efforts to evacuate workers believed to be trapped inside the tunnel at Samardung in the Jholungey area of Namchi district.
Officials said the operation remains underway with multiple agencies working in coordination under difficult conditions.
The latest development comes a day after an emergency unfolded inside the under-construction tunnel following a landslide, which reportedly triggered a suspected gas leak and blocked portions of the tunnel, complicating rescue efforts.
On Monday, authorities announced that 16 workers trapped inside the tunnel had been rescued safely after a massive multi-agency operation. The workers were evacuated from the tunnel near Mamring, close to Rangpo, and shifted to the Primary Health Centre (PHC) in Rangpo for medical examination and treatment.
However, fresh official information released on Tuesday confirmed seven fatalities in connection with the incident.
Authorities have not yet clarified whether the deceased were among the previously rescued workers or rescue personnel, and further details are awaited.
The rescue operation has involved personnel from the Sikkim Police, Fire and Emergency Services, district administration and other emergency response agencies. Rescue teams have been working round-the-clock amid concerns over hazardous gases and unstable conditions inside the tunnel.
During Monday's operation, members of a rescue team from neighbouring West Bengal reportedly suffered dizziness and briefly lost consciousness after suspected exposure to toxic gases while attempting to enter the tunnel. They were immediately evacuated and provided medical treatment.
The Samardung tunnel is part of the NHPC's Teesta Stage VI Hydroelectric Project, one of the key hydropower projects under development in Sikkim.
Authorities are expected to conduct a detailed investigation to ascertain the exact cause of the incident after rescue operations are completed and the site is declared safe. Construction activities are likely to remain suspended until a comprehensive safety assessment is carried out.
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