over a week. But the colonial authorities realised that the independence struggle had become too powerful to ignore. Underground struggle After Dunkirk, the British colonial authorities reacted in panic (as revealed in secret files released many decades later) and N. M. Perera, Philip Gunawardena and Colvin R. de Silva were arrested on 18 June 1940 and Edmund Samarakkody on 19 June. The LSSP press was raided and sealed. Regulations were promulgated which made open party work practically impossible. However, the experience gained in hiding Bracegirdle now paid off. The cover organisation of the LSSP, of which Doric de Souza and Reggie Senanayake were in charge, had been active for some months. Detention orders had been issued on Leslie Goonewardene but he evaded arrest and went underground. The LSSP was involved in a strike wave which commenced in May 1941 affecting the workers of the Colombo Harbour, Granaries, Wellawatta Mills, Gas Company, Colombo Municipality and the Fort Mt-Lavinia bus route. With Japan's entry into the war, and especially after the fall of Singapore, Sri Lanka became a front-line British base against the Japanese. On 5 April 1942, The Japanese Navy bombed Colombo. That evening, in the confusion following the attack, the LSSP leaders were able to escape, with the help of one of their guards. Several of them fled to India, where they participated in the independence movement there. However, a sizeable contingent remained, led by Robert Gunawardena, Philip's brother. In 1942 and 1944 the LSSP gave leadership to several other strikes and in the process was able to capture the leadership of Government workers’ unions in Colombo. Cocos Islands mutiny The fall of Singapore and the subsequent defeat and sinking of the battleship and the battle cruiser , punctured the propaganda of British invincibility. The credibility & prestige of the British was further damaged by the sinking of the aircraft carrier and the cruisers and off Sri Lanka in early April 1942; accompanied at the same time by the virtually unopposed bombing of mainly the British colonial bases in the island and bombardment of Madras (Chennai). Such was the panic amongst the British in Sri Lanka that a large turtle which came ashore was reported by an Australian unit as a number of Japanese amphibious vehicles. The Ceylon Garrison Artillery on Horsburgh Island in the Cocos Islands mutinied on the night of 8/9 May, intending to hand the islands over