OSLO (Reuters) -Sweden's coast guard discovered a fourth gas leak on the damaged Nord Stream pipelines earlier this week, a spokesperson told the Svenska Dagbladet newspaper. The European Union suspects sabotage was behind the gas leaks on the subsea Russian pipelines to Europe and has promised a "robust" response to any intentional disruption of its energy infrastructure. "Two of these four are in Sweden's exclusive economic zone," coast guard spokesperson Jenny Larsson told the pa...