On 25 March 1973, the Sarawak government, led by chief minister Abdul Rahman Ya'kub started to clamp down on communist activities at the Rajang basin by setting up "Rajang Special Security Area". A day later, Rajang Security Command (RASCOM) was formed as a result of co-operation of civil, military, and police command headquarters. By August 1973, several communist members were captured by the government. The captured members provided crucial details for the government to further impair the communist movement. On 22 September 1973, Abdul Rahman started "Operation Judas". A total of 29 people from the town of Sibu were captured. Among those captured were doctors, lawyers, businessmen, teachers, and one former member of parliament. Following the surrender of a communist movement in Sri Aman on 21 October 1973, the communist activities at Rajang basin began to subside and would not be able to recover to its previous strength. Communist movement of Sarawak finally ended in 1990.