WALTHAM, Mass. (MyFoxBoston.com) -- Fire officials in Waltham say at least 20 people were taken to a hospital as a precaution because of a carbon monoxide leak at a local Sunday school.
Firefighters responded to St. Mary's Religious Education Center on Pond Street Sunday morning. They initially received a call for a natural gas leak, then detected the high levels of the potentially deadly and odorless gas.
"We found about 20 that initially were saying they had some type of a medical issue between light-headedness and a headache," said Michael Quinn, Waltham's deputy fire chief. "So we declared a mass causality incident and brought in paramedics to evaluate each one of the children."
Officials said there were no serious cases of carbon monoxide poisoning and everyone taken to Newton-Wellesley Hospital was expected to be OK.
"I felt like a little dizzy, but when I got out of the building, I felt better," said Amber Castriotta, who had been inside a classroom in the center.
Most of the people taken to the hospital were students ages 8 to 12. At least 17 students were taken to the hospital from a classroom that had roughly 50 children in it.
"Carbon monoxide is a byproduct of burning. So the boilers were running, so if there was a blockage in the chimney or a cracked fire chamber that would explain why we have such high levels of carbon monoxide," Quinn said.
Officials were not saying if carbon monoxide detectors were in the building or even required. Quinn told FOX 25 their investigation is ongoing and the building's boilers are being checked.
The school's heating system is shut down as investigators work to determine the cause of the leak. Services at St. Mary's continued on Sunday, though the school is expected to be closed for a few days.