Adelaide police have charged two teens who were allegedly planning a Columbine-style massacre that targeted school students and staff.
Police say the boys, aged 16 and 18, planned to use guns, explosives and knives to massacre students and staff at a Riverland high school.
A search of the 16-year-old's home uncovered the materials to build a makeshift bomb.
They allegedly shared their plan with students, who tipped off police.
Both teens are facing serious charges and remain in custody without bail.
The local community is shocked at the allegations.
"It is really, really scary," local resident Shayle Reid told Adelaide Now.
"It's shocking - who would think anything like this would ever happen in Australia."