Several opposition parties such as the Pan-Malaysian Islamic Party (PAS), the Democratic Action Party (DAP) and Parti Keadilan Rakyat (PKR) have spoken out against the ISA. Many of them have leaders or prominent members who were held under the ISA, such as Mohamad Sabu of PAS, Lim Kit Siang, Karpal Singh and Lim Guan Eng of the DAP, and Anwar Ibrahim of the PKR. Previously in the 1960s, the law had been denounced by such opposition leaders as Tan Chee Khoon, who said: