On 20 January 1942 the Japanese 15th Army, comprising two divisions, commanded by Lieutenant General Shojiro Iida, swept across Burma's border with Thailand near Moulmein, to the east of Rangoon (see Map 2). The invaders travelled lightly, for they could bring little of the machinery of modern war with them along the jungle tracks on the remote Thai side of the border. They had to seize Rangoon quickly in order to bring in the supplies and heavy reinforcements they needed to subdue and occupy Burma. Meanwhile they would have to live and fight with what they could carry or capture. By the use of cunning, aggressive manoeuvre the Japanese swept around and over early British resistance, and Rangoon fell on 8 March 1942. By that time a Chinese Expeditionary Force (CEF), approximately the numerical equivalent of a British corps, had intervened in order to help defend the one remaining overland supply route to China, which ran through Burma. The combined British and Chinese Burma Army then attempted to hold central and north Burma in order to maintain contact between India and China. Over the following two months, however, the Japanese forced the allies relentlessly northwards until they were forced to split and withdraw from the country into Assam and China. Meanwhile, following the fall of Singapore, two Japanese naval striking forces under Vice Admiral Ozawa and Vice Admiral Nagumo, who had led the raid on Pearl Harbour, sortied out into the Bay of Bengal, attacking Ceylon and ports on the east coast of India. The Japanese sank two British cruisers and an aircraft carrier, along with over 90,000 tons of allied merchant shipping. With the bastion of Britain's prewar defence plans for the Far East and the last overland route to China lost, India then found herself unexpectedly on the front line of the war against Japan whilst also having to transform herself into being the strategic base for all further operations in that theatre.