The operator of the Nord Stream 1 gas pipeline from Russia to Europe has sent a ship to Swedish waters to investigate the background of a unexplained blast that damaged it several weeks ago. Nord Stream AG announced on Thursday that the chartered, specially equipped vessel arrived at the suspected site of the damage and specialists would be ready to explore the damage within a day. The investigation will take roughly three to five days, it added. The company did not have the relevant permits until now. Unexplained blasts in late September caused four gas leaks in the Nord Stream 1 and 2 gas pi…