Deputies are patrolling the West Muskingum Local Schools after the district received a third threatening letter Friday morning.
According to school officials on the district's Facebook page, a threatening letter was found at West Muskingum High School on Friday.
The letter was not mailed, and due to the delivery method, content and style of the letters, detectives said they did not believe the letter was related to two other letters received by the district earlier this week.
School officials said Friday afternoon that the person who left the letter was identified and that the school was taking appropriate action.
On Thursday, the district received its second threatening letter. The letter was sent to the West Muskingum Middle School.
The middle school also received a letter in the mail on Wednesday.
The investigation into the other two letters was still ongoing.
The district said it has been in close contact with the Muskingum County Sheriff's Office.
Anyone with information is asked to call the sheriff's office at 740-452-3637.
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April 18, 2013:Middle School Receives Second Threatening Letter