The bodies of all 25 workers killed in the collapse of an under-construction tunnel in Sikkim’s Namchi district were recovered on Thursday, bringing a nearly 96-hour search and rescue operation to an end.
The tunnel collapse occurred on Monday afternoon at Adit-3, a section of the 15-km-long tunnel being constructed as part of the NHPC Teesta Stage VI Hydropower Project. The tunnel connects the barrage at Sirwani with the powerhouse at Tarkhola in South Sikkim.
Officials suspect that a methane gas explosion triggered the disaster, while toxic gases and difficult conditions inside the tunnel slowed rescue efforts.
By Wednesday night, rescue teams had recovered 22 bodies. Three more bodies were found during Thursday’s operation, taking the death toll to 25. A final inspection of the tunnel was later conducted, and officials confirmed that no workers remained trapped inside.
Teams from the National Disaster Response Force (NDRF), State Disaster Response Force (SDRF), Sikkim State Disaster Management Authority (SSDMA) and specialised rescue units from West Bengal’s coal mining belt were involved in the operation.
Officials said the recovered bodies were sent to hospitals in Singtam, Gangtok and Namchi for medico-legal procedures.
The Sikkim government has also formed a high-level committee to investigate the incident and determine the circumstances that led to the deadly tunnel collapse.
