 This raid was intended to secure newly conquered Burma, Malaya, and the Dutch East Indies against Allied attack by destroying base facilities and forces in the eastern Indian Ocean.On 26 March 1942, the five carriers of the First Air Fleet departed from Staring Bay; they were spotted by a Catalina about southeast of Ceylon on the morning of 4 April.Nagumo closed to within of Colombo before launching an airstrike the next morning.