Prussing Elementary School View Full Caption DNAinfo/Heather Cherone

JEFFERSON PARK — A carbon monoxide leak at Prussing Elementary School in Jefferson Park that sickened 71 students and seven adults was caused by a faulty boiler, Chicago Public Schools officials said in a statement late Friday.

In a message to parent Sunday posted on the school's website, Principal George Chipain said the school would reopen for class Monday morning after two carbon monoxide detectors had been installed on every floor of the school.

None of the injuries were serious, officials said.

An investigation is underway to determine the specific cause of the incident at Prussing, 4650 N. Menard Ave., according to a statement from CPS officials. The boiler was last inspected July 27, officials said.

The Local School Council planned to hold an emergency meeting at 7 p.m. Monday to discuss the incident and the school's response, officials said.

While the statement from CPS officials said staff members "worked diligently to keep parents informed throughout the day" parents and council members said the lack of information from officials left them panicked and angry.

In a Facebook post, council member Phil Huckelberry, who raced to the school just after the leak was discovered at 9:30 a.m., called the response by school officials "highly chaotic."

Problems with the school's boiler have been well known for years, and have been the subject of complaints filed by school officials with city leaders, said Huckelberry, who questioned whether the school had working carbon monoxide detectors.

Assistant Principal Hanna Kapica was one of the seven adults sickened by the carbon monoxide, Huckelberry said.

"The communications situation was just not good overall," Huckelberry said. "Parents are very angry. A lot never got the robocalls."

Students not affected by the carbon monoxide were taken to Smyser Elementary School, 4310 N. Melvina Ave.

The symptoms of carbon monoxide poisoning can include headaches, weakness, dizziness and nausea. Significant poisoning can result in vomiting, shortness of breath, confusion, blurred vision and loss of consciousness.

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