More than 200 people were at the Garfield Park pool Thursday afternoon when they were exposed to a toxic brew of acid and chlorine used to clean the pool, RTV6’s Jack Rinehart reported.

Hazmat crews were called in after dozens of adults and children began vomiting and suffering from breathing problems, scratchy throats and watery eyes.

Medical responders quickly surveyed the victims and determined those most in need of medical attention. Nearly an hour-and-a-half later, emergency crews transported 67 victims to area hospitals.

Many of the victims were treated and later released, but officials said eight people remained hospitalized late Friday.

"I would say overall, (there was a) great response by every agency that participated, focusing on the safety of the patient, the safety and well-being of the public, moving them to definitive care expeditiously. Everybody who participated did a wonderful job,” said emergency official Carl Rochelle.

Emergency officials called the spill a mass casualty event because of the overwhelming number of people sickened within the first few minutes of the incident.

Indy Park officials said the cause of the spill remained under investigation.