A teenage boy has been charged after an alleged “copycat threat” made during HSC exams last week.

Around 30 schools were thrown into chaos after they received threatening emails over two days which forced the evacuation of staff and students.

A day later, a single phone call was made to a school in North Sydney, which police say was “inconsistent” with the other incidents.

Police say the North Sydney incident is unrelated to the other incidents.

A teenager was arrested this morning in a southern Sydney home, and police allege the teen spat on an NSW Police Force employee during the arrest.

Police Minister David Elliott told Jim Wilson he was horrified at the allegation.

“That is an offence in itself, an offence we are looking at toughening up.”

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