Guwahati, July 22: Rescue teams battling toxic gases and hazardous conditions entered the third day of operations on Wednesday after a suspected methane gas explosion inside an under-construction hydropower tunnel in South Sikkim claimed 20 lives, making it one of the state’s deadliest industrial accidents.
The tragedy unfolded on Monday at the ADIT-3 tunnel of the NHPC Teesta Stage-VI Hydroelectric Project at Samardung in Namchi district, where a sudden release of methane gas trapped inside rock formations is believed to have triggered an explosion. The blast filled the tunnel with dense smoke and poisonous gases, trapping 25 workers and project officials.
According to Namchi Superintendent of Police Sonam D. Bhutia, 20 of the 25 people trapped are now feared dead, while five remain stranded deep inside the tunnel. Rescue personnel have recovered 12 bodies, seven of whom have been identified.
The deceased include four workers from Jalpaiguri in West Bengal and one each from Assam, Punjab, Uttarakhand’s Dehradun and Namchi in Sikkim.
The rescue effort has been severely slowed by the presence of toxic gases inside the tunnel. Officials said several rescuers experienced dizziness and breathing difficulties while attempting to reach the trapped workers, highlighting the dangers faced by emergency personnel.
Multiple agencies, including the National Disaster Response Force (NDRF), State Disaster Response Force (SDRF), Sikkim Police, Fire and Emergency Services, district administration and a specialised mining rescue team from West Bengal, are working round the clock to stabilise the tunnel environment and continue the search.
Authorities have yet to confirm the exact cause of the explosion, but preliminary assessments indicate that excavation work may have punctured methane pockets trapped within the rock, triggering the deadly blast.
The tunnel forms part of the Teesta Stage-VI Hydroelectric Project, where investigations into the cause of the accident are expected once rescue operations are completed.
