RCMP were called to Chilliwack senior secondary shortly after noon on Thursday after a message found in the school contained a "veiled and non-specific threat."
But police are not disclosing any details about the content of the threat.
"The school wasn't put in lockdown but kids were kept safe in their classrooms," said RCMP Cpl. Tammy Hollingsworth. "Police took precautions, with high visibility at the school."
CSS students were released more than two hours later, classroom by classroom, and the investigation is ongoing.
"A lockdown is only put in place when there's an active shooter, or a threat of an active shooter," the officer said.
Earlier in the day, the students had been practising routine lockdown procedures, she said.
jfeinberg@theprogress.com
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