INDIANAPOLIS -- Dozens of people at a crowded public swimming pool were sickened Thursday by an excessive amount of a water-purifying chemical in the pool, authorities said.
The Garfield Aquatics Center was evacuated after a reported chemical spill.
The chlorine-based purifying chemical, called "Magic Acid," caused nausea, coughing and watery eyes among the swimmers, many of them children, and 71 people were taken to hospitals, Todd Harper of the Indianapolis Emergency Services said.
Twenty-one were taken by ambulance and another 50 by bus, NBC station WTHR reported.
All were listed in fair condition, and none of the injuries were considered life-threatening, he said.
It's believed the chemicals were dumped into the water around 2 p.m.
Marc Lotter, a spokesman for the mayor's office, said the incident was caused by a chemical imbalance in the pool. WTHR reported it's believed that a muriatic acid product reacted with a chlorine-like substance to treat the pool. Officials are investigating whether or not a worker mixed the chemicals incorrectly.
The incident closed the center for the rest of the day.
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