Socio-political repression by the regime of the Shah likewise increased in the 1970s. As an authoritarian government, the Shah centralised the political power completely. The lack of political freedom led to massive discontent. At the time, the majority of the Iranians were excluded from political participation. Opposition parties such as the National Front and the pro-Soviet T?deh Party were marginalised or outlawed as well. With Iran becoming a single-party state, the social and political stability were purely depended on Shah’s secret police, the SAVAK, which was assisted by CIA and Mi6. Every corner of society was subjected to surveillance, censorship, and political supervision. Shah’s dictatorial ruling and loss of legitimacy resulted in the withdrawal of popular support from the Shah and in the development of serious opposition which threatened his reign.