The Special Duties Unit (Abbreviation: SDU; Chinese: 特別任務連, nicknamed Flying Tigers 飛虎隊) is an elite paramilitary tactical unit of the Hong Kong Police Force. Established in July 1974, it is a sub-division of the Police Tactical Unit (PTU). Its primary functions include counter-terrorism, hostage rescue and dealing with crimes (usually involving firearms) which are considered too dangerous for regular police to handle.