Forty-three children were rushed to an Atlanta hospital and treated for carbon monoxide poisoning after a leak of the deadly but invisible and odorless gas was detected at an elementary school.
In addition to the children, six adults became sick following a leak that is believed to have originated from a leaky furnace, according to fire department officials.
The Atlanta Fire Department received a call around 8:30 a.m. reporting that several students and teachers at Finch Elementary School in south Atlanta felt sick.
When hazardous material crews arrived, they did not find any unconscious individuals but found dangerously high levels of carbon monoxide gas.
"The highest levels were near the furnace, but they were high throughout the school," Capt. Marian McDaniel, the fire department spokeswoman, told ABC News.com.
Gas levels peaked at 1,700 parts per million, the highest fire officials "had ever seen," according to McDaniel.
The entire school was evacuated. Some 500 children were checked for signs of illness and taken to a nearby middle school. The 43 sick children were taken to Children's Healthcare of Atlanta at Hughes Spalding. The six adults were taken to Grady Memorial Hospital.
Some of the sick children have already been discharged from the hospital. The school is expected to reopen Tuesday.