A boy has been arrested and cautioned after students at a Catholic school were locked down over a "threatening" post on social media that sparked a police investigation.
St Bede's College in Melbourne's southeastern suburb of Mentone was plunged into lockdown for about an hour on Wednesday morning.
The school's principal, Deb Frizza, confirmed all staff and students were safe.
Victoria Police said detectives investigated a "threatening" social media post.
Police said on Wednesday night that a 17-year-old boy was arrested in relation to the post that "allegedly made possible threats towards a teacher from a bayside school".
The boy was released from custody and given a caution.
