INDONESIANS demanded at the start of the International People’s Tribunal yesterday that the “vicious cycle of denial” about the country’s 1965 coup and massacre must end.

Nursyahbani Katjasungkana, an Indonesian rights activist and former MP who helped set up the tribunal, said the government in Jakarta needed to be held to account for crimes committed in the past.

“The Indonesian government is responsible to fulfil and respect victims’ rights,” she said. “They have the right to justice, the right to truth and reparations.”

In 2012 Indonesia’s National Human Rights Commission released a report concluding that the mass killings constituted gross human rights violations. However, the government dismissed it and refused to examine it further.

The killings began in September 1965 when a group of suspected coup-plotting generals were assassinated by army officers loyal to president Sukarno, who had irritated Western powers with his independent economic policies.

The instability was exploited by anti-Sukarno generals, including eventual dictator General Suharto, to launch a campaign against the massive Indonesian Communist Party (PKI).

The US, Britain and Australia aided Suharto’s slaughter of communists, supplying arms and other support — with the CIA accused of providing a kill list to Indonesian officers.

In formerly secret British files officials admit the attack on the PKI was “a struggle basically for the commanding heights of the Indonesian economy.”

About 500,000 people are believed to have been killed.

The tribunal is expected to issue verdicts, which are not legally binding, next year.