MEK is accused of detonating a bomb at the Islamic Republican Party headquarters on On 28 June 1981 . The incident , called Hafte Tir bombing in Iran , killed 73 , including Mohammad Beheshti , the party 's secretary-general and Chief Justice of Iran , 4 cabinet ministers , 10 vice ministers and 27 members of the Parliament of Iran . Two days later after the incident , Ruhollah Khomeini accused the MEK . According to a Reuters dispatch in the New York Times on June 30 , 1981 , " the authorities initially blamed the ' Great Satan ' ( the US ) . " Ervand Abrahamian noted that the Islamic Republic " also suspected ' SAVAK survivors and the Iraqi regime . " According to The Times , the Nationalist Equality Party claimed credit for the attack . The pro-Soviet Tudeh part was also suspected . According to The Times " a note had been found saying the Forghan group … had staged the attack " . Within days , the regime changed story and blamed the MEK . " MEK did not admit responsibility for the attack . According to Kenneth Katzman , " there has been much speculation among academics and observers that these bombings may have actually been planned by senior IRP leaders , to rid themselves of rivals within the IRP " . According to Ervand Abrahamian , " whatever the truth , the Islamic Republic used the incident to wage war on the Left opposition in general and the Mojahedin in particular " . According to the U.S department of state , the bombing was carried out by the MEK . A Kermanshah tribunal executed four " Iraqi agents " for the incident , and a tribunal in Tehran executed Mehdi Tafari for the same incident . According to The Times , the Nationalist Equality Party claimed credit for the attack , and that " a note had been found saying the Forghan group … had staged the attack
Hafte Tir bombing
Hafte Tir bombing
People's Mujahedin of Iran