South-east Asia faces new threat of youth extremism

Elsewhere, the picture is similarly varied. Philippine police’s Anti-Cybercrime Group told senators in August that they had handled 74 cases of nihilistic violent extremism – where extreme violence is pursued without a clear political or religious ideology – and rescued 42 minors, 30 of them aged 15 or younger.

Filipino cybersecurity expert Angel Redoble told the hearing that vulnerable children could be drawn in on ordinary platforms such as games before being moved into private servers or encrypted messaging apps.

“The algorithm learns what each user responds to and serves them progressively more of it,” he said. “It has become a weapon.”

In Malaysia, newer online pathways have surfaced alongside the more familiar threat from ISIS.

Six males aged 16 to 21, including three minors, were arrested in February 2026 over alleged ISIS-linked activities.

Officials said several had encountered violent content through games before moving on to private messaging apps. The authorities have not disclosed how many teenagers have been detained in Malaysia over alleged extremism or terrorism-related activities, but officials said recurring vulnerabilities among young people in such cases included bullying, social isolation and troubled family backgrounds.

Drawing the line on extremism

As the lines between ideological extremism, violent online subcultures and personal grievances become less clear, the authorities across the region face the same question: When does troubling behaviour become a security threat requiring intervention?

Malaysian criminologist Haezreena Begum Abdul Hamid from Universiti Malaya said getting that distinction right is crucial.

“If we get the diagnosis wrong, we get the response wrong. And once we start calling every troubling act terrorism, we risk both over-securitising young people and failing to understand what is actually driving the violence,” she said.

Alif said the authorities may need to look beyond ideology for warning signs, including growing isolation, deeper engagement with violent material and a shift from consuming such content to actively participating in violent online communities.

But such signs do not necessarily point to extremism. Criminologist Trynh Phoraksa of Mahidol University in Thailand said grievances, social isolation and exposure to extremist narratives could interact differently for each individual.

“None of these factors alone means that somebody will become a terrorist,” he said.

Thailand most recently dealt with this on Aug 7, when a 14-year-old student shot dead his grandparents at home before opening fire at Debsirin Nonthaburi School outside Bangkok, killing five others before taking his own life.

Investigators found that he had viewed violent online material and developed an interest in guns, while a Nazi flag was found at his home.

But police also uncovered family problems, academic pressure and conflicts with friends. They found no evidence linking the Nazi imagery to the shooting or the teenager to an extremist group.

Experts said this case highlights how difficult it can be to distinguish genuine security threats from other troubling behaviour, as many warning signs can appear in young people who are not extremists.

Moving the fight upstream

The shift also creates an institutional problem – cases that do not clearly meet the threshold for terrorism can fall between counter-terrorism agencies, schools, child protection services and mental health professionals.

This is pushing prevention further upstream, towards the parents, teachers, counsellors and friends who are often best placed to spot changes in a young person’s behaviour before they escalate.

But identifying someone earlier is only part of the challenge, and observers said the authorities also need to rethink how to intervene when the young person may not hold a coherent extremist ideology in the first place.

Much of Indonesia’s state-led deradicalisation programme focuses on changing an individual’s ideology, including through former terrorist ideologues and religious counselling. But many of the newer cases involve young people without strong ideological commitments, Alif said.

“So, we need to rethink what CVE looks like for individuals drawn into violent online communities,” he added.

Across the region, the authorities are experimenting with different ways to respond. In Malaysia, the six young people arrested in February are undergoing a programme combining religious guidance with critical-thinking and ethics training aimed at reintegrating them into society.

There is also greater emphasis on detecting problems before they reach that dangerous stage. In Indonesia, Densus 88 worked with the education authorities in Cirebon in May 2026 to train 142 guidance and counselling teachers, known as Guru BK, to protect junior high students against online radicalism and to look out for behavioural red flags.

But ISEAS – Yusof Ishak’s A’an said such efforts were not yet widespread, with gaps remaining in supervision by schools and parents.

Singapore’s experience suggests those closest to young people can play a critical role. ISD said the majority of young people it investigated had displayed signs of radicalisation to people around them, particularly family and friends, before coming to the authorities’ attention.

Someone at the school of the 14-year-old detained in June alerted the authorities after noticing his interest in violent videos, while friends of a 19-year-old tried to dissuade him from his extremist beliefs before informing ISD.

Philippine experts have similarly called for parents to better understand their children’s online lives, advised teachers to recognise signs of isolation or distress, and emphasised the need for stronger school counselling services.

“After parents, (schools) are the next eyes on the children every day,” Senator Risa Hontiveros of the Philippines told ST.

The challenge, experts stressed, is to widen this safety net without making ordinary teenage behaviour a reason for suspicion.

Thomas Koruth Samuel, an expert on preventing violent extremism for the United Nations Development Programme, said prevention should also focus on building young people’s digital literacy and critical thinking. This can create what he described as “mental firewalls” against extremist messaging.

Young people should be treated as partners in prevention rather than simply as potential security threats, he said.

Alif said the emergence of violent online communities would require South-east Asian countries to adapt their approaches, but the region has decades of experience to draw on.

“South-east Asian states are not necessarily starting from scratch,” he said. “The region has three decades of experience developing and implementing CVE responses to jihadist terrorism.”

While existing approaches could not simply be transferred wholesale, he added, lessons could be adapted, “particularly the importance of building alternative social ties and providing young people with sources of belonging and purpose outside extremist milieus”.

The aim, he said, should include helping vulnerable young people build new social ties that give them “a sense of belonging, purpose, and self-worth beyond that of their violent milieus”.