SYDNEY, Dec 6 (Reuters) - One in five priority

counter-terrorism cases investigated by Australia involved

youth, the country's spy chief said on Friday, as the "Five

Eyes" intelligence partners warned about the radicalisation of

young "digital natives".

Mental health, education and social services needed to

intervene in many cases before the behaviour of minors became a

police issue, said a research paper by the Five Eyes, which also

include the U.S., Canada, Britain and New Zealand.

"Around 20% of ASIO's priority counter-terrorism cases

involve young people. In every one of the terrorist attacks,

disruptions and suspected terrorist incidents in Australia this

year, the alleged perpetrator was a young person," Australian

Security Intelligence Organisation (ASIO) Director-General Mike

Burgess said in a statement.

"As a parent, the numbers are shocking. As an intelligence

officer, the numbers are sobering," he said.

The Australian Federal Police (AFP) had investigated 35

teenagers aged 17 years or younger, including a 12-year-old, in

terrorism investigations since 2020, said AFP Commissioner Reece

Kershaw.

Over half of them were charged with offences, he said.

In one Australian case described in the report, a

16-year-old involved in a local and international network shared

violent extremist material calling for attacks on non-Caucasian

people, and "urged others to prepare for an upcoming race war to

'defend the white race'".

The teenager had few real-world relationships and spent

little time socialising offline, it said. He was arrested and

sentenced to 18 months jail.

In another Australian case, a 14-year-old with nationalist

and racist extremist views used a Snapchat account to plan a

violent attack, and after being arrested by police undertook

programmes on countering violent extremism.

"We are witnessing the same extremist propaganda videos

across multiple unrelated investigations, and this suggests that

links exist in the online environment across platforms such as

Discord, Telegram and TikTok," said Kershaw.

Australia passed legislation this month to ban children

under the age of 16 years from social media platforms starting

late next year.