The high school students were evacuated and moved next door to Roger Ludlowe Middle School.
At least four fire engines responded to the scene at the high school at about 10:30 a.m. Thursday.
There was a problem with the HVAC unit on the roof that pumped smoke into the music room of the high school at 785 Unquowa Road, according to NBC Connecticut. No injuries were reported.
Read the full story here at NBC Connecticut's website.
This story will be updated as more information becomes available.
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