A police spokeswoman said officers were called to the Musselburgh school, which can not be named for legal reasons, shortly after 9am this morning.
The spokeswoman said: “At no point was a pupil or a member of staff threatened or harmed.
“A report will be submitted to the Children’s Reporter and officers continue to liaise with the school and local authority surrounding this.”
East Lothian Council said: “At no point was any child in our school community at risk. We are cooperating fully with Police Scotland.”
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