Sikkim Tunnel Collapse: 12 Workers Dead, Rescue Operation Underway

At least twelve workers lost their lives when a section of a tunnel under construction to channel water from the Teesta River to a nearby hydropower plant collapsed on Monday. The collapse followed a sudden burst of methane gas, which caused an explosion and a rush of toxic fumes into the confined space.

The National Disaster Response Force (NDRF) reported the incident approximately 1.5 kilometers inside the tunnel. Rescue operations are now focused on a 200‑metre stretch where the remaining thirteen people are believed to be trapped.

The tunnel is part of a larger project managed by the state-owned National Hydroelectric Power Corporation (NHPC). Officials have stated that the explosion was caused by methane gas combustion “in confinement” which is a known risk in tunnelling through methane‑rich rock.

Out of the 27 workers who were inside the tunnel, two escaped while the remaining twenty‑five were trapped. Police have identified seven victims, including one local worker from Sikkim and others from West Bengal, Uttarakhand, and Assam. The cause of death will be confirmed through post‑mortem examinations.

Chief Minister Prem Singh Tamang has formed a special investigation team to determine the exact cause of the collapse and to review safety measures. The investigations will also assess whether the guidelines for handling methane‑heavy environments were followed.

This accident underscores the challenges of infrastructure development in the Himalayas, where underground gas pockets can pose significant hazards. Similar incidents worldwide have prompted stricter regulatory oversight and the adoption of advanced gas‑detection technologies in tunnelling projects.