Derby High School and the preschool within the school are dismissing early on Monday due to an electrical issue.
District officials said earlier in the morning, there was an odor in the school that turned out to be an electrical issue.
According to the district, the students were initially evacuated, but are now going home for the day.
The preschool that is located within the school is also dismissing for the day.
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It's unclear if the school will reopen as scheduled on Tuesday.