CHICAGO (WLS) — A child died and another is in serious condition after being exposed to carbon monoxide on the city’s Northwest Side, according to sources.

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Chicago police said they first responded to the call at 5:17 a.m. at a three-story building in the 3000-block of West Gunnison Street in Albany Park.

A 10-year-old girl was found unresponsive on the third floor. She was taken to the hospital, where she died, according to Chicago police.

Sources tell ABC7 Chicago a 12-year-old boy from the same home was also taken to the hospital in serious condition.

The children were exposed to high levels of carbon monoxide, sources told ABC7.

Rhoda Maliet, a mother of four, also lives in the building. She said she woke up to police rushing her out of her home into the cold.

“It’s too much for me to process because I know them very well, and they are a young family,” Maliet said. “Police were knocking on our door, and they were saying, ‘get up. Get up. Get up, and get out.'”

She added that other families in the building were also sent to the hospital as a precaution.

“If that was a sickness, you know what killed your baby, but this one is just a sudden death, and it’s really so sad,” Maliet said.

Sources said three other adults were also sent to the hospital.

A “do not enter” sign was on the front door later Monday.

“I’m really feeling devastated because these were young kids, and it’s beyond words,” neighbor Tina Carroll said.

A People’s Gas spokesperson released the following statement:

“We were asked to come to the address as part of standard protocol. There is no reason to believe the cause of the issue is related to any of our equipment. The Chicago Fire Department is leading the investigation.”

The Chicago Fire Department Monday afternoon stressed the importance of having working carbon monoxide and fire detectors in homes, calling carbon monoxide the “silent killer.”

“There is no sight or smell to it. So, you can have a small leak in your furnace or in your kitchen, somewhere that could be undetected,” CFD said.

Chicago fire officials did not say if there were working carbon monoxide detectors in the home or building.

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