An official with Ridgefield Public Schools says that police responded to the high school at 700 N Salem Road after a written threat was received.
The nature of the threat is unclear.
School officials say that out of an abundance of caution, students and staff were dismissed at 9:30 a.m.
The early dismissal and threat does not affect Scotts Ridge Middle School on the same road.
The incident remains under investigation at this time.
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