Manchester, NH- A family of seven in Manchester, N.H., was taken to the hospital Sunday night after a “life-threatening” amount of carbon monoxide leaked from their home’s gas-operated heater, according to fire officials. A family member at the Auburn Street apartment called authorities around 6:30 p.m. Sunday, complaining that several people had headaches and nausea, said Manchester Fire District Chief Mike Gamache. One person was unconscious when firefighters arrived, he said.

“We monitored the air, and found the carbon monoxide levels to be extremely elevated, at a life-threatening amount,” Gamache said. “If they disregarded their feelings and went to bed, we would have had seven fatalities in the morning.” The family, whose members ranged in age from 9 to 64, was taken to Catholic Medical Center in Manchester. Five family members were expected to remain overnight, Gamache said.