Gangtok, July 21: At least 10 people were killed and several others are feared trapped after an under construction tunnel of the Teesta Stage VI Hydroelectric Project collapsed in Sikkim's Namchi district on Monday.

The incident was triggered by a landslide, with officials suspecting that a methane gas explosion inside the tunnel worsened the collapse. The debris blocked the tunnel entrance, making rescue efforts extremely challenging.

Teams of the National Disaster Response Force, State Disaster Response Force, police, and other emergency agencies have launched a massive rescue operation to locate and evacuate the trapped workers. However, continuous rainfall has severely hampered the operation by causing further instability in the surrounding terrain. The presence of toxic gas inside the tunnel has also posed serious risks to rescue personnel.

Authorities are monitoring the situation closely as efforts continue to reach those trapped inside the tunnel.

Prime Minister Narendra Modi expressed grief over the tragedy and announced an ex gratia of Rs 2 lakh from the Prime Minister's National Relief Fund for the next of kin of each deceased. The injured will receive financial assistance of Rs 50,000.

Further details are awaited as rescue operations remain underway.