A teenage girl was arrested after allegedly carrying a knife onto Trident High School grounds, prompting the school to go into lockdown for about an hour yesterday afternoon.

Police were called to the school at about 12.20pm following reports of a fight or altercation.

“There were no injuries reported,” police said.

“A teenage girl was arrested for possession of an offensive weapon and breach of bail.”

Police said the weapon was believed to be a knife. The teenager was due to appear in Whakatāne District Court today.

Trident High School principal Mikaere October said the person arrested was not a student but a member of the public who had entered the school grounds.

“We had a member of the public who came onto the school site who posed a threat,” he said.

“So, we made the call to go into lockdown as a precaution to make sure everyone was safe. That’s why we have our lockdown procedures.”

The school remained in lockdown from about 12.20pm until 1.20pm while staff ensured the situation had been resolved.

October said the school had recently practised its lockdown procedures.

He said the incident appeared to be unrelated to the school and stemmed from matters outside the school community.

“Once we knew there was a threat, we went into lockdown. The person wandered through the school grounds, as members of the public sometimes do, moving from classroom to classroom.”

Staff and students had locked themselves in their classrooms.

After police had dealt with the situation, students gathered in the school auditorium before classes resumed.

“We take the safety of our students and staff seriously,” October said.

The incident was unrelated to a series of emailed threats received by schools and other organisations around New Zealand yesterday.

Detective Inspector Glenn Baldwin of Auckland City CIB said police were investigating a number of threatening emails sent to schools and institutions nationwide.

“At this stage, police perceive the threats to be low risk,” he said.

“The Cybercrime Team, supported by staff in other police districts, has initiated an investigation and is working to determine the source of the emails.”

Anyone with information is asked to contact police through 105 online or by phone, or anonymously through Crime Stoppers on 0800 555 111.