SAN JOSE (CBS SF) – Emergency responders in San Jose transported 35 victims to area hospitals from a South Bay swim club after they were sickened by gas created by an accidental mixture of pool chemicals, according to authorities.

The incident was reported at about 12:10 p.m. at Shadow Brook Swim Club, located at 1079 Shadow Brook Drive off of Almaden Expressway, according to Santa Clara County Fire Capt. Bill Murphy.

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The county fire department is assisting San Jose firefighters in the response to the hazmat situation, which resulted from some mixture of pool chemicals that caused people to report nausea, vomiting, trouble breathing and other symptoms, Murphy said.

Investigators said a pool worker put the wrong chemicals in the wrong places.

“We don’t know if it was the muriatic acid that got put into the chlorine or the chlorine put into the muriatic acid. But what it did do is produce a yellow cloud. That cloud was a toxic cloud,” said San Jose Fire Capt. Mitch Matlow. “That maintenance worker was exposed. That cloud spread out to the pool and the pool deck, so everyone out there was also exposed.”

Victims had to be stripped and hosed down with fire hoses behind blue tarps to wash away the contamination. Parents and children as young as six were exposed to the toxic cloud at the Almaden Valley swim club.

“I took a deep breath and realized there was definitely something poisonous,” said lifeguard Lindsay Tarasco. “So I rushed all the kids to the side exit and got everyone out and they started throwing up. Everyone started coughing and no one could breath. A couple kids were on the ground and were very dizzy. We called 911.”

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Most of the victims were transported to nine different hospitals in ten ambulances that responded to the scene. San Jose fire officials did not have specifics on the conditions of the victims.

San Jose’s specially equipped hazmat team first had to decontaminate the victims with water.

The victims, mostly in their teens and 20’s, later donned white hazmat suits as they waited for ambulances to take them to the hospital.

The fire department says the incident could have been fatal.

“Muriatic acid and pool chlorine when they mix together make chlorine gas. Chlorine gas has been used as a weapon in the past,” said Matlow. “Anybody who is exposed to it can have potentially life threatening injuries even if they don’t have symptoms right away.”

Fire officials said that most of those victims who were taken to area hospitals were treated and released.

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