“Then they created new accounts and spread the same kind of content. It means no matter how strong we try to stop them, hack their social media accounts, they will rise again and create new accounts again.

“We must raise public awareness, we must protect our people, and don’t let them get provoked by their massive spread of ideology in social media.”

Hukom’s comments come as survivors and relatives of friends of victims prepare to travel to Bali to mark two decades since the bombings, which killed 202 people including 88 Australians.

The anniversary has approached amid outrage about former JI bomb maker Umar Patek being made eligible for parole last month after serving only 11 years of a 20-year prison term.

Prime Minister Anthony Albanese expressed concern about reducing the sentence of Patek, who admitted to mixing chemicals used in the Bali attacks, and he remains in jail in East Java with his early release yet to be signed off by President Joko Widodo’s government.

Yasonna Laoly, Indonesia’s minister for law and human rights, has made clear Jakarta would only consider objections to Patek being freed from Indonesian institutions not external voices.

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Hukom’s police squad endorsed his release, believing him to have been fully reformed, but he said Indonesia owed much to Australia for strengthening its counter-terrorism forces and its “workplace culture”. The two countries last year renewed an anti-terror intelligence sharing pact.

“We’ve learnt a lot from them since the 2002 Bali bombing,” said Hukom, who arrested Bali bomber Amrozi a month after the attack. “At that time, we understood nothing. We didn’t have the technology, we didn’t know what kind of [terror] network it was. They taught us. They even helped us with investigation technology.”

Speaking at a seminar at the University of Indonesia this week, he added: “Honestly, our approaches now have vastly changed, [the capability] of our intelligence now is extraordinary.”

Adhe Bhakti, a terrorism expert at the Centre for Radicalism and Deradicalism Studies in Jakarta, said the introduction in 2018 of comprehensive anti-terrorism laws had given police and Indonesia’s National Counter-Terrorism Agency, BNPT, much greater scope to arrest suspects.

“I think we can say they are successful given the significant drop in the number of terror attacks,” he said.

“The counter-terrorism law allows law enforcers to arrest people before they carry out their crime as long as law enforcers have proof that they plan to do an attack or are involved in terrorism activities.”

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