ROUND ROCK -- A marching band competition at Round Rock ISD's Kelly Reeves Sports Complex quickly turned serious as several students and one adult started suffering from the afternoon heat.
Around 4 p.m. on Saturday, Austin-Travis County EMS started receiving emergency calls for patients suffering from symptoms of heat exhaustion.
13 people were treated at the scene and four had to be taken to area hospitals, all with minor injuries.
EMS officials said other students were moved to air-conditioned buses where they were able to eat and stay hydrated.
Cedar Ridge High School was hosting the competition that brought 23 other high schools from across the state. 3,500 students attended the competition and RRISD had a doctor on the scene throughout the day.