During World War II, Commonwealth Security Service was formed in 1941 to investigate organisations and individuals considered likely to be subversive or actively opposed to national interests; to investigate espionage and sabotage; to vet defence force personnel and workers in defence-related industries; to control the issue of passports and visas; and was responsible for the security of airports and wharves, and factories engaged in manufacture of munitions and other items necessary for Australia’s war effort. It was also responsible for radio security. In June 1945 it produced a report warning of the danger of the Communist Party of Australia.