'Threatening' social media post sparks Melbourne school lockdown

A school in Melbourne's south-east was briefly placed into lockdown this morning following reports of a "threatening social media post".

St Bede's, a Catholic all-boys secondary school at Mentone, was forced into lockdown at 8.25am, and was lifted an hour later.

Principal Deb Frizza told 9News that "all students and staff were safe".

The principal said the lockdown followed advice from Victoria Police.

"St Bede's College Mentone commenced lockdown on the advice of Police as part of a Police Operation," Frizza told 9News.

"At 9.40am the lockdown was lifted, and classes have resumed as normal. Thank you to all our community for your cooperation and understanding."

Detectives said they were investigating a threatening social media post, which was reported about 11pm last night.

"The post did not include threats against any particular school or person," police said.

"Investigations to determine who created the post are underway. There is currently no threat to St Bede's College in Mentone."