A landslide tore through the hillside above an under-construction road tunnel in Sikkim's Namchi district on Monday afternoon, burying the entrance of the passage under a wall of debris and trapping at least 27 workers who were deep inside the Samardung tunnel at the time. The collapse triggered panic in the surrounding area, and the district administration scrambled to launch a rescue operation within minutes of learning what had happened. Complicating an already dangerous situation, officials suspect a methane gas leak has built up inside the sealed tunnel, adding a fresh layer of risk to every attempt to reach the trapped men.
27 workers accounted for, alert came in at 3:40 pm
Namchi District Collector Anupa Tamling said her office is still working to pin down the exact number of people trapped inside, since workers were spread across different points of the tunnel when the entrance gave way. Early information suggests the trapped group is made up of 21 employees of Patel Engineering and 6 employees of NHPC, adding up to a total of 27 men. The district administration first got word of the collapse at around 3:40 pm on Monday, and rescue teams were dispatched to the site almost immediately, with the operation now running on a war footing to bring everyone out alive.
Methane gas and a cramped passage are slowing the rescue
Officials believe the landslide shook loose underground rock layers, and that this movement may have released methane gas that had been trapped naturally beneath the surface, allowing it to seep into the sealed tunnel. The presence of that gas, combined with the tunnel's narrow bore and near-zero visibility once the entrance was blocked, is making every metre of the rescue slower and riskier. Several rescue workers who pushed inside in search of the trapped men have reportedly started feeling dizzy soon after entering, and some have even fainted, a sign of just how thin and hazardous the air inside has become.
NDRF, SDRF and more join the effort, echoes of the 2023 Uttarkashi collapse
Teams from the National Disaster Response Force, the State Disaster Response Force, the district police, and fire and emergency services are all now working the site round the clock. A specialised unit equipped with gas-resistant gear has also been rushed in from West Bengal to help with the operation. Ambulances have been kept on standby near the site, and rescuers are trying to push further into the tunnel wearing gas masks and other protective gear despite the conditions. The scramble echoes 2023, when 41 workers were trapped for roughly two weeks inside the Silkyara tunnel in Uttarkashi, Uttarakhand, in a similarly nerve-wracking ordeal before a painstaking operation finally brought all of them out alive.
The tunnel is part of NHPC's Teesta Stage-6 hydropower project
According to officials, the tunnel where Monday's collapse happened is an ADIT tunnel, essentially an access passage being dug for NHPC's Teesta Stage-6 hydroelectric project, with the construction work being carried out by Patel Engineering. The district administration has made clear that its entire focus for now is on bringing all 27 trapped workers out of the tunnel safely, with every other consideration set aside until the rescue is complete. Only once the men are out will authorities turn to a detailed investigation into exactly what triggered the landslide and how the methane build-up occurred inside the passage.
