Bunbury Police were called to Newton Moore Senior High School at 1pm on Thursday to remove a female student who was acting aggressively.
The Mail understands the school was placed into lockdown after a student carrying a wooden pole began to threaten others.
School principal Kylie Cattaway sent a letter home to parents on Thursday night to say rumours the student was armed with a knife were untrue.
“To help with managing the situation students were retained in class for approximately thirty minutes delaying the beginning of the lunch break,” she wrote.
“The school and administration staff acted immediately to protect students and staff while the incident was diffused.
“At no time were any students in danger.”
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