Aotea College in Porirua was put into lockdown just before noon today after the school received a threat, according to police and the school's Facebook page.
The threat came as students were taking exams, or were coming to take them this afternoon.
Police were notified of a text threat sent to the college around 10:30am and told to school to go into lockdown.
NZQA exams for Level 1 Music, Level 2 Accounting and Level 3 History were cancelled today, students being asked to take them at nearby Mana College.
Aotea College says students will be able to apply for derived grades if impacted by today's incident, including those taking tests tomorrow.
"Any students unable to attend exams on Thursday 10 November due to the effects of today's lockdown will need to contact the school, we will then give them further advice on how they can apply for a derived grade."
Police left the school just before 4pm and are confident there is no safety risk.
They are now looking to identify anyone involved with threat.
"We’re aware of the distress this would have caused in the school community, and thank everyone for their co-operation today."
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