In the spring of 1939 Japanese intelligence officers led by Suzuki Keiji had arrived in Yangon posing as journalists in order to gather information and to seek the cooperation of local parties for the intended Japanese invasion of Burma, occupying an office at 40 Judah Ezekiel Street for that purpose. Among their network of local collaborators they made close connections with the "Thakins", of which Aung San was a leading member. The familiarity of Japanese intelligence with prominent political actors in Burma ensured that they were aware of Aung San's activities by the time he arrived in Japanese-occupied China. Suzuki was later forced to leave Burma after the British learned of his activities in October 1939, but vowed to return.