The killings of at least half a million Indonesians who were accused of being communists is being publicly discussed for the first time in 50 years.

Up until now, government leaders have not revealed exactly what happened during one of the darkest periods of Indonesian history.

Researchers estimate that half a million or more communists, and people accused of supporting them, died in those years - killed by soldiers and some religious groups that had an anti-communist agenda.

Survivors have come from all over Indonesia for this historic opportunity.

Never before have victims of the communist purge in the mid-1960s been asked to speak at a government symposium.

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"The government of Joko Widodo is reaching out to us and I happily accept the gesture as long as our main principle is upheld that the truth will be told and justice will be done," said Sri Sulistiawati, a former prisoner.

Mass graves from the massacre are scattered across the country but Indonesians have always been kept in the dark over what really happened.

The army ordered the killings after seven generals were murdered in what was seen as a failed coup in 1965, which was blamed on the communists.

One of those killed was the father of Agus Widjojo, a retired general who told Al Jazeera it was about time the government dealt with its past.

"This case has been in our past for 50 years now," Widjojo said.

"We haven’t been able to solve it as a nation. Where are we going if the nation is still divided and doesn’t want to make any effort to find a solution?"



The events of 1965 continue to be a sensitive subject.

When survivors tried to hold a meeting to prepare for next week's symposium, a conservative group known as the Islamic Defenders Front threatened to attack the gathering.

Conservative groups - often backed by the military - have long resisted any discussion of the killings.

The survivors are asking for a special court to be set up to hear those accused of the 1965 killings.

However, the Indonesian government favours a process of "national reconciliation", saying those who orchestrated the violence five decades ago have already died.

Human rights groups have insisted that the truth about what happened must be told.