Crowley Fire Department responded to a report of multiple unconscious patients at Richard Allie Middle School on Saturday night.
The building was evacuated with the help of Crowley ISD and police, according to Crowley FD.
An event, not being hosted by the district, was taking place at the middle school.
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The City of Crowley confirmed this was a heat-related incident, and four people were treated on the scene and one person was transported for further treatment.
Crowly ISD confirmed that the air conditioner was functioning properly during the event.