East Lyme — Students temporarily were evacuated or diverted from the middle school Friday morning because of a heating unit malfunction, Administrative Assistant Stacy Watson said in an email to parents.

Watson said the rooftop unit created a strange smell in the building when it malfunctioned. Students who were in the school or who had yet to get there were sent to the Lillie B. Haynes School to wait while firefighters investigated.

Watson said students returned to the middle school when firefighters gave the all clear.