Philadelphia, PA- Fire officials say a carbon monoxide detector, required by law in Philadelphia, may have saved eleven lives Friday morning.

A carbon monoxide alarm went off at a home in the 5600 block of Warrington in Southwest Philadelphia.

Medics arrived to find nearly a dozen people overcome by fumes.

They rushed the two adults inside to the hospital. Soon, they found the source of the colorless, odorless, highly toxic gas in the basement of the row home next door.

“They had a portable generator running without any ventilation,” said Battalion Chief Derrick Sawyer of the Philadelphia Fire Department. “They

had the electric turned off and they were supplying the electric from this portable generator.”

Inside that home, four adults and three children were feeling the effects of carbon monoxide poisoning. They, too, were transported to the hospital along with two adults in the next house down.

Lisa Bell’s mother is one of the carbon monoxide victims. Bell’s husband bought the CO alarm for his mother-in-law last year.

“He works for the electric company. We have them all throughout our house too, so we wanted to make sure she was safe too,” she said.

All eleven victims from this morning’s scare were checked out and released from local hospitals late this morning.

A law requiring at least on working carbon monoxide detector in all Philadelphia homes went into effect in January.