Six people, including two children, suffered carbon monoxide poisoning symptoms Monday morning at the Llanberris Apartments at 101 Conshohocken State Road in Bala Cynwyd, Pa., firefighters said.
Around 8:45, the victims were found out front of Building C with symptoms related to CO poisoning, officials said.
The two kids and three of the adults were rushed to the hospital while the sixth victim refused treatment, officials said.
A search revealed no more victims but all buildings at the complex were evacuated, according to authorities.
Crews did however find high levels of carbon monoxide inside three of the five buildings at the complex, they said.
A faulty heater or too much pressure coming into the building were believed to be responsible for the CO. PECO and firefighters remained on the scene Tuesday afternoon to investigate.
By 4:45 p.m. residents were allowed back into all units except for those in Building C, officials said.
No firefighters were hurt during the incident.
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