A spate of threatening phone calls to schools this week have similarities, a top police officer says, with the current theory being they are computer-generated and could have come from offshore.
Eighteen schools have received threats this week - five on Tuesday and 13 on Thursday - leading many to head into self-imposed lockdowns or to evacuate students and staff. A police investigation is now underway, though officers don't believe there is a safety risk.
Comparisons are being made to a 2016 incident when about 30 schools were the recipients of threatening recorded messages from overseas.
Speaking to AM on Friday morning, Assistant Commissioner Bruce O'Brien said the calls are thought to be computer-generated and have been directed to schools' main lines. Staff have then been assessing the level of threat and then implementing their own emergency plans.
"We have had a number of schools around New Zealand over the few days receive phone threats, which we believe are computer-generated," he said.
"These threats are of a nature that have caused enough concern by the schools to either go into lockdown or evacuate the school.
"We are working really closely with the schools to provide that reassurance, but also we are looking into where the origins of these calls are and we are working through potentially are they offshore or have they occurred from New Zealand."
New Zealand police are working with international authorities on the origins of the threats and are committed to holding those responsible accountable.
The threats received by schools were "to cause harm to students and staff at the school. They are of a very similar nature. It is known that these have mentioned explosive devices," O'Brien said.
Principals' Federation President Cherie Taylor-Patel told RNZ on Thursday she had spoken to Iona Holsted, the Education Secretary at the Ministry of Education, and it is their understanding the threats are being received from "a cyber bot coming in from overseas".
O'Brien told AM these types of calls all usually have a similar threat.
"They go out to a whole lot of different places over a very small period of time. They are designed to cause concern, harm, and disruption, and we obviously saw that with schools around New Zealand yesterday."
He believes the perpetrator wants to "cause the disruption to the school and obviously concern".
"It is really concerning that a person or persons think this is an appropriate way to conduct themselves."
O'Brien acknowledged the distress being caused to the school communities and said the incidents were being taken extremely seriously.
Chris Hipkins, both the Education Minister and Police Minister, told reporters on Thursday schools have plans to deal with these types of events and were being supported by the Ministry of Education and police.
"It is concerning, it is an incredibly challenging thing for schools to have to face," Hipkins said.
He had a clear message to those behind the calls: "Don't be idiots."
