Students told the Bay of Plenty Times they were told to get under desks and classroom curtains were drawn during the incident.
"It was very dramatic for Aquinas."
Despite earlier reports from students, a police spokeswoman said there was no assault and no knife.
Asked whether there was any weapon involved, she said police had no further comment as they had not yet spoken to the students involved.
Neither police nor the principal responded specifically to a student report that the intrusion was sparked by a relationship issue involving the boyfriend of a student.
Dalton provided a written statement describing the incident as a "relatively minor episode" and an earlier media report was inaccurate.
He said the girls involved were aged 13 and 14.
"While the incident was unpleasant, I am pleased with the way the College's systems designed to handle emergency situations ensured an efficient response."
He said the procedure was designed for any incident that could be deemed threatening to students and staff.
"It was determined this was a necessary step in the interests of the health and safety of our students and staff. Police were called and dealt with the situation in a professional manner."
