FORT WASHINGTON, Md. (AP) — Prince George’s County police say a family of five is in critical condition after being exposed to high levels of carbon monoxide in their home.

Police say the family was found unconscious in the 8300-block of Bernard Drive in Fort Washington about 12:30 a.m. Tuesday.

Authorities say they were called to the home by doctors at Children’s National Medical Center in Washington. Police say the doctors were treating a child who lives at the home and discovered high levels of carbon monoxide in the child’s blood.

The family of five, including two parents and three children, were taken by helicopter to a Baltimore hospital.

Police say they believe a malfunctioning natural gas furnace in the home was to blame for the carbon monoxide.

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