At least 10 people were killed and 17 others remain missing after a suspected gas explosion triggered a collapse inside an under-construction tunnel at a hydropower project in India’s northeastern Himalayan state of Sikkim, near the Chinese border, officials said on Tuesday. The blast ripped through the tunnel on Monday at Samardung village, about 40km (25 miles) from the state capital, Gangtok, where multiple workers were carrying out construction work on the 500-megawatt Teesta hydroelectric...