There are additional police officers at Waterbury Career Academy High School on Tuesday as a threat is investigated.
Police said the threat was made on social media and involved a school identified as "Career."
Officers are working with the school administration and parents have been notified.
Additional police officers will be at the school throughout the day on Tuesday. There are currently no lockdowns or other restrictions in place at the school, according to police.
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The investigation is ongoing.
Anyone with information is asked to contact the Waterbury Police Detective Bureau at (203) 574-6941 or the Crime Stoppers anonymous tip line at (203) 755-1234.