On Monday afternoon, East Haven police began investigating a possible bomb threat at the high school.
Police said the threat was made during school, which was distributed through text message and social media.
The school was evacuated and the New Haven Police Regional Bomb Squad was dispatched to assist.
Police searched the building and cleared it at 1:50 p.m.
No injuries were reported and no arrests are pending.
The incident, police said, appears to be a misinterpretation of a comment made earlier in the day.
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