The leader of the hardline Islam Defenders Front (FPI), Muhammad Rizieq Shihab, has threatened to attempt to impeach President Joko "Jokowi" Widodo if the latter agrees to make a state apology for the mass violence that occurred in 1965, as demanded by human rights activists and families of the victims.

The apology is sought as part of a reconciliation process to settle gross human rights violations that occurred during the 1965 communist purge.

"If President Jokowi apologizes, we and all Muslims in the country will impeach him," Rizieq told an audience including retired high-ranking military generals during an event entitled the National Symposium on Securing Pancasila From the Threat of the PKI (Indonesian Communist Party) and Other Ideologies on Wednesday.

Speaking in a high and fiery tone that he usually reserves for delivering sermons, Rizieq further warned, "We will oppose anyone, including state officials, who instigates the rebirth of the PKI."

In his speech, he also slammed Coordinating Political, Legal and Security Affairs Minister Luhut Binsar Pandjaitan for what Rizieq said was a slow and indecisive response to "the rampant use of communist symbols".

Several retired Army generals attended the two-day event that began on Wednesday, including former vice president Try Sutrisno and retired Army general Kivlan Zein. The event, held to commemorate the birth of Pancasila on June 1, was arranged to challenge a previous state-sponsored national symposium held to bring together and gain input from various stakeholders, including victims, human rights activists, academics and state officials, as part of efforts to come up with comprehensive solutions to settle the human rights abuses that happened during and after the mass killings in 1965.

It is estimated that around 500,000 people were killed and millions sent to prison without trial in the 1965 tragedy. The growing calls for justice for victims and their families have met with protests from several civil groups warning both the government and the public about the rise of communism in the country. (rin)