Dozens treated for heat-related illnesses at Heritage Day Parade in Placentia

PLACENTIA, Calif. (KABC) -- The Heritage Day Parade in Placentia was halted Saturday after 61 people fell ill in triple-degree heat, Orange County Fire Authority officials said.

Twenty people were transported to area hospitals. The victims included children, parade participants in heavy band uniforms and spectators, OCFA spokesman Larry Kurtz said.

The temperature reached up to 105 degrees during the annual event. Firefighters from OCFA, Brea, Anaheim and Fullerton responded to the scene and set up a triage area.

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Common symptoms of heat-related illnesses include nausea, headaches, and fatigue.

"As a result of the high humidity and the high temperatures, you have to hydrate," Kurtz advised.