Essex, MD – WBAL-TV -A man and two teenage girls died of apparent carbon monoxide poisoning Monday inside their Essex home.

Norman Sylvester Wiley, 48; Sheriesa Bernay King, 15; and Ja-Na Liett Jones, 14, were pronounced dead at the scene Monday afternoon, Baltimore County police said.

Adrian Wiley, 35, the mother of the two girls and Norman Wiley’s husband, was treated at the University of Maryland Shock Trauma Center and released.

Adrian Wiley called 911 shortly after noon and reported that she had awakened and was ill, and the rest of her family members were unconscious. When firefighters arrived, their carbon monoxide detectors found high levels of the odorless gas, police said.

Investigators found that a vent pipe leading from a water heater was misaligned, and that could have led to the release of carbon monoxide. With temperatures in the 90s, the family had an air conditioner running and the windows and doors closed, which would have prevented fresh air from getting inside.

Autopsies will be conducted, but police have no reason to suspect anything but carbon monoxide poisoning, said Bill Toohey, a police spokesman.

Firefighters evacuated 26 units in the Hopkins Creek townhouse complex for several hours Monday afternoon while they tested to make sure the area was safe.