The Ontario Provincial Police (OPP) say that a 16-year-old has been charged after a "threatening message" was discovered at a high school in Lambton County.
On Thursday, police were called to Lambton Central Collegiate and Vocational Institute in Petrolia after the message was found in a washroom.
The accused, who lives in Plympton-Wyoming, was arrested Monday and has been charged with uttering threats and mischief.
Police have not specified the nature of the threat but said such incidents are taken seriously.
"The OPP recognize the importance of school safety and how a threat of this nature can be difficult for all who are affected," the police service said in a statement.
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