A half-century after at least half a million people were killed in a brutal pogrom against suspected communists and communist sympathizers, Indonesia is still unsure about whether it is ready to glance at — let alone actually face up to — one of the darkest chapters in its history.

On Monday, Indonesia’s Chief Security Minister Luhut Panjaitan will open a two-day, government-backed national symposium in Jakarta on the 1965–66 killings. Supported by the National Human Rights Commission, the event is expected not only to discuss the killings but also plans to facilitate the first meeting between members of the Indonesian military, which led the anticommunist persecution, and survivors of the atrocity.

An estimated 500,000 to 1 million people — some say even millions — perished as the army, paramilitary groups and religious organizations hunted down members of the Indonesian Communist Party (known as PKI, which was blamed for the deaths of six army generals), suspected leftists, supporters and their families. Ethnic Chinese were targeted too because of the party’s close ties with Beijing. In addition, hundreds of thousands of political prisoners languished behind bars or toiled in far-flung gulags.

Among the architects of the conference are Sidarto Danusubroto, a member of the presidential advisory committee, and Agus Widjojo, a retired general whose father was one of the high-ranking army officials who, according to the official version, were allegedly killed by the PKI.

“It is to guarantee that we will not repeat in the future what had happened — forgive but not forget,” said Agus, co-founder of Forum Silaturahmi Anak Bangsa, an umbrella organization that seeks to facilitate dialogue and reconciliation between children of ex-PKI members, the families of army generals killed in 1965 and other victims of conflicts.

(Read: The Memory of Savage Anticommunist Killings Still Haunts Indonesia, 50 Years On)

However, the symposium’s focus on reconciliation, while remaining reticent on the facts of what happened, has sparked criticisms from human-rights activists who have long called for a full and frank approach to the massacre on the part of the state.

Nursyahbani Katjasungkana, a human-rights lawyer and activist who was one of the coordinators of the International People’s Tribunal on the 1965 massacre, held in the Hague last year, welcomes the symposium on one hand, hoping that it “will facilitate a national dialogue” toward reconciliation. “But,” she adds, “finding the truth is a prerequisite.”

Days before the national conference, two human-rights groups, the New York City–based Human Rights Watch and the Jakarta-based Kontras, made a joint call for the U.S. to release secret files on the 1965 massacres. “We want to know the working level involvement between the U.S. government and the killers in 1965,” HRW executive director Kenneth Roth told journalists in the Indonesian capital on Wednesday.

Although the fall of authoritarian President Suharto in 1998 has unleashed a certain level of openness on the massacre, it remains a controversial topic. It is not uncommon for any activists seeking to address the human-rights violations of the 1965-66 victims and survivors to be harassed and intimidated by Islamic hard-liners or members of the security forces.

(Read: Movies, Books Push Indonesia to Confront Its Bloody Past)

This was what happened to one group that is scheduled to take part in the national seminar next week. The Research Foundation on the Victims of the 1965/66 Killings (YPKP 65) was forced to relocate its preparatory meeting for the symposium on Thursday following harassment by Islamic hard-liners, said YPKP 65 chairman Bejo Untung. He also said military intelligence interrogated the group’s members before they even arrived in Jakarta.

“The government or the state, especially the military, shouldn’t repress or intimidate us,” Bejo told online radio station Portal KBR. “We are very disappointed because until today, the victims of the 1965 [tragedy] are threatened whenever they hold a meeting.”

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