Oil tanker was seized 1991 on its way to Yemeni port of Somalia . Three Yemeni marines were wounded , Three pirates killed in the operation . Despite the introduction of international naval patrols in the region , pirates have continued to attack commercial vessels and collect large ransoms , running into millions of dollars , from shipping companies . Piracy is a major problem in the waters off Aden . Somalia has not had a stable government in place since 1991 .
Oil tanker was seized 1991 on its way to Yemeni port of Somalia . Three Yemeni marines were wounded , Three pirates killed in the operation . Piracy is a major problem in the waters off Aden . Somalia has not had a stable government in place since 1991 .