Before the PMOI could become operational, it was penetrated by SAVAK, the Shah's secret police. A safe house was discovered, which led to the identity of several members. Their interrogation and torture, in turn, generated additional names and arrests.
By September 1971, SAVAK had rounded up and imprisoned about 150 PMOI members, including the group’s founders and members of the Central Committee. Sixty-nine Mojahedin were brought before military tribunals and charged with attempting to overthrow the monarchy and other offenses.
The PMOI was unknown at the beginning of the tribunal trials, which were initially open to the media. The resistance organization quickly became a household name and was celebrated for its efforts to bring democracy and freedom to Iran. After members publicly disclosed they had been tortured while in custody of SAVAK, media coverage was terminated.
All of the PMOI’s leadership, including its founders and members of the Central Committee, were executed or imprisoned. Massoud Rajavi's death sentence was commuted to life imprisonment after an international campaign organized by Dr. Kazen Rajavi, Mossoud's brother who lived in Geneva, and the intervention of top French officials.
Without a leadership structure, the PMOI floundered. Its remnants were taken over by pro-communists, who usurped the organization’s name and remaining assets. Low-level PMOI members were offered the choice of either supporting the new leadership and ideology or being expelled. In some cases, they were murdered.