Fifteen Indian workers were feared trapped on Tuesday after a blast caused by a suspected gas leak in a tunnel at a hydroelectric project in the rugged state of Sikkim killed 10, authorities said.Monday’s incident took place at state-owned National Hydroelectric Power Corp’s (NHPC) project on the Teesta river in the northeastern state’s village of Samardung, district official Subash Ghimirey said.A sudden burst of gas suspected to be methane trapped or embedded in rocks in the tunnel caused...