Gangtok: Fresh information emerging from the Samardung tunnel tragedy in Sikkim's Namchi district indicates that the incident may have been caused by a methane gas explosion during excavation rather than a landslide, as initially reported, with rescue teams recovering 10 bodies and continuing the search for workers still feared trapped.
According to sources at the project site, the incident occurred when excavation work struck rock formations containing trapped methane gas, triggering an explosion that was followed by a massive methane gas leak inside the under-construction tunnel.
The gas rapidly spread through the tunnel, leaving workers with little chance to escape and severely hampering rescue operations. Rescue personnel who initially entered the tunnel were forced to retreat due to the high concentration of methane before they could reach those trapped inside.
The workers feared trapped are from different parts of the country, including Jharkhand, Assam, Punjab and Jammu & Kashmir.
Sources said this was not the first methane gas leak reported inside the tunnel. A similar incident allegedly occurred around four months ago, but it was relatively minor, with a few workers reportedly sustaining first-degree burn injuries to their hands.
No one was trapped in that incident. Monday's tragedy, however, is believed to have been far more severe because of the reported methane explosion and the number of workers caught inside.
Further indications supporting the methane explosion theory emerged after rescue teams recovered bodies bearing extensive burn injuries rather than injuries associated with being buried under debris.
Sources said the victims were not found trapped beneath collapsed earth or rocks, lending weight to reports that the incident was triggered by a methane gas explosion during excavation rather than a landslide.
The Samardung tunnel is part of the under-construction Teesta Stage VI Hydroelectric Project in Namchi district. Initial reports on Monday had suggested that a landslide inside the tunnel had trapped workers and triggered a methane gas leak, making rescue operations extremely hazardous.
Sikkim Chief Minister Prem Singh Tamang has informed that the authorities have constituted a Special Investigation Team to probe the cause of the tunnel disaster. The Chief Minister has announced an ex-gratia of four lakh rupees for the families of the deceased, and fifty thousand rupees for those injured.
As of 9.30 am on Tuesday, rescue teams had recovered 10 bodies from the tunnel. The deceased have been identified as Bolo Oraon and Gora Oraon, both from Jalpaiguri in West Bengal; Yasohal from Pathankot, Punjab; Vikey Rawat from Dehradun, Uttarakhand; Bikesar Oraon from Jalpaiguri, West Bengal; Babul Borodalai from Assam; and Lakpa Dorjee Tamang from Katang in Namchi. Three other bodies remain unidentified.
The bodies have been shifted to Namchi District Hospital, STNM Hospital and Singtam District Hospital for further procedures.
Another National Disaster Response Force (NDRF) team has entered the tunnel to continue search and rescue operations for the remaining workers feared trapped.