Gas Explosion Kills 10 and Traps 17 in Sikkim Tunnel Collapse

A suspected gas explosion on Monday killed at least 10 workers and left 17 missing after collapsing an under-construction tunnel at the 500-megawatt Teesta hydroelectric project in Samardung village, Sikkim, where rescue teams are now working. Multiple crews were inside the tunnel roughly 40 kilometers from Gangtok near the border with China when the blast occurred.

Survivors described a loud explosion followed immediately by falling debris.

Six officials from the state-owned National Hydroelectric Power Corporation who entered the tunnel to help rescue efforts became trapped themselves. Local police chief Sonam Dolma stated on Tuesday that teams had recovered 10 bodies so far, with 17 others feared trapped. Rescue operations involving the National Disaster Response Force have been slowed by hazardous conditions inside the tunnel.

NDRF official Nitin Kumar reported finding toxic gases including methane, carbon monoxide and hydrogen sulphide, which forced rescuers to use specialized breathing equipment. The Teesta River basin sits in a seismically active region with young, fragile rock formations. Dr.

Devesh Walia, a geology professor at North-Eastern Hill University, said the area contains relatively young rock formations associated with coal-bearing strata, making it possible that accumulated methane triggered the explosion. Construction accidents remain common in India's Himalayan region, where fragile geology and seismic activity increase risks for tunnel projects.

A similar collapse in Uttarakhand state in 2023 trapped 41 workers for 17 days before their rescue.