Five people died at the plant before they could be taken to the hospital, and another died in the emergency room.

A liquid nitrogen leak in a poultry factory in the state of Georgia killed six people Thursday and several more were rushed to hospital, officials said.

Beth Downs, a spokeswoman for the Northeast Georgia Health System, said five people died at the Gainesville plant before they could be hospitalized, while one person died in the emergency room.

Hall County’s Fire Department chief Zach Brackett said firefighters reacted to the leak after 10 a.m. at Prime Pak Foods.

“When the units arrived, they found a large contingent of staff who had been evacuated along with several victims who were in that crowd and who were also experiencing medical emergencies at the facility,” Brackett told reporters on a televised report Press conference.

Brackett said firefighters, the U.S. Department of Occupational Health and Safety and the state firefighter were investigating what happened. Poultry farms rely on cooling systems that can contain liquid nitrogen.

“It was a leak of unknown origin that occurred in the system,” Brackett said. “We still have a lot of information we’re trying to gather from the scene.”

Sean Couch, another health system spokesman, said of the nine other injured patients, three were admitted to Gainesville Hospital in critical condition. Five were treated in the emergency room and were in good condition. One was on his way to the emergency room when Couch spoke.

At least four firefighters were injured and taken to hospital by Brackett with “breathing difficulties”.

Brackett said about 130 workers were taken by bus to a nearby church where they were examined for injuries. Couch said a person was taken to the hospital from there.

Hall County school officials said the students were being kept safe at a nearby elementary school, saying the leak was contained and not in the air. Approximately 2.5 km (1.5 miles) of a road in front of the plant and school has been closed.

Prime Pak Foods merged with Foundation Food Group, a company that turns raw chicken into products such as chicken fingers and individual pieces of chicken for restaurants and hospitality establishments. The company’s CEO did not immediately respond to a call asking for comment.

Gainesville is the center of Georgia’s largest poultry industry, with thousands of employees working for multiple processing plants.