The Internal Security Act 1960 (ISA) of Singapore is a statute that grants the executive power to enforce preventive detention, prevent subversion, suppress organized violence against persons and property, and do other things incidental to the internal security of Singapore. The present Act was originally enacted by the Parliament of Malaysia as the Internal Security Act 1960 (No. 18 of 1960), and extended to Singapore on 16 September 1963 when Singapore was a state of the Federation of Malaysia.