At least 10 schools in New South Wales and Victoria have been placed in lockdown or evacuated their students after a series of threats were made on Friday.
An automated threatening phone message was received around 11am by NSW schools including Mona Vale Public School, Woolooware High School, St Monica's Primary School Richmond and Penrith High School.
"Police are aware of numerous threats made to schools in the Metropolitan and Southern Regions," NSW Police announced after midday.
"Investigations are continuing, and police are liasing with the Department of Education."
Victorian schools were also evacuated or placed in lock down including Berwick Lodge Primary School, Berwick Chase Primary School, Aitken Creek Primary School, Resevoir High School and Cowes Primary School on Phillip Island were evacuated.
"We're aware that a number of Victorian schools have received a threatening phone call today. They're being evacuated as a precaution," Victorian police posted to Twitter.
"We are aware that schools in a number of other states and countries have received similar phone calls in the past 24 hours."
@ResignInShame The police operation has concluded. Investigations are continuing into the threats.— NSW Police (@nswpolice) January 29, 2016
Students are returning to Aitken Creek Primary School in Craigieburn after an evacuation to the local library.— Seb Costello (@SebCostello9) January 29, 2016
parents are reportedly hysterical after hearing about the evacuation. New year 7 students just started school yesterday.— Merryn Porter (@Merryn_Porter) January 29, 2016
So there's a bomb threat right now as I type in Reservoir High. Is any of us students scared honestly no, we are treating this as a joke.— Michael J Russo (@Mickster112233) January 29, 2016
Reports of several schools in Vic being evacuated b/c of bomb threat including Berwick Chase PS #Melbourne— Megan Bailey (@MeganLeaderNews) January 29, 2016
Police all over reservoir high school.— Sherie (@shceni) January 29, 2016
Information regarding police operations at numerous schools pic.twitter.com/8MkCV5m0c3— NSW Police (@nswpolice) January 29, 2016