 In 1962 Indonesia launched a significant campaign of airborne and seaborne infiltrations against the disputed territory, beginning with a seaborne infiltration launched by Indonesian forces on 15 January 1962.The Indonesian attack was comprehensively defeated by Dutch forces including the Dutch destroyers "Evertsen" and "Kortenaer", the so-called .Amongst the casualties was the Indonesian Deputy Chief of the Naval Staff; Commodore Yos Sudarso.