New Zealand’s spy agency has released a public guide on how to spot the early warning signs of a violent extremist, as they grapple with an increasing amount of alarming behaviour online.

The Security Intelligence Service says children have started joking about terror attacks on social media, causing a headache for those trying to weed out the serious threats.

Joining us now is the director of the International Centre for the Study of Violent Extremism Anne Speckhard. Anne has interviewed more than 800 terrorists, violent extremists and their family members through her career.

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