Seven bodies have been recovered from a tunnel construction site after a landslide damaged it and led to a gas leak in Sikkim, officials said. About 20 others are feared trapped, they said. Teams of the National Disaster Response Force (NDRF) are carrying out rescue and search operations. The incident happened in South Sikkim's Samardung tunnel at 3.09 pm on Monday. Patel Engineering is constructing a section of the Teesta Stage VI Hydroelectric Project here. According to preliminary information, a landslide inside the tunnel blocked the passage and trapped several workers. Rescue efforts were further complicated by a suspected methane gas leak, making it unsafe for personnel to reach the affected section.