"When our guys went in, they found the couple unconscious. They removed the couple from there to the front yard."
In the yard, crews worked to revive them. That's when neighbors became truly scared.
"They were just convulsing like they were having epileptic attacks. That's what it looked like because it was that severe."
Neighbors stood by helplessly.
"She was even foaming at the mouth and, uh, it was quite scary. I'd never seen anything that bad before."
Other witnesses say the couple was making home repairs and didn't have utilities hooked up, so they were running a generator in the basement.
"I mean, the first thing I thought was carbon monoxide."
Authorities confirm there were high levels of CO fumes. They say the generator in the basement was cold when they arrived, so it had to have stopped running a few hours before.
"Calls with readings this high are pretty rare."
It's something the crew didn't take lightly.
"Firefighters who responded to the scene last night had one of these on them. It's a four-gas monitor. It sends out an alarm when carbon monoxide levels hit 35 parts per million, but, keep in mind, last night's call had levels as high as 500 - 1,000 parts per million."
They opened doors and windows and used fans to clear the air, but still levels were alarmingly high.
"They didn't have a carbon monoxide detector which is required by law."
The couple was taken to Decatur Memorial Hospital then transferred to a different hospital. Their condition is not known.
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