ROCKVILLE, Md. -- A woman rescued from a house fire Thursday morning in Rockville died.
Montgomery County fire officials say crews arrived early Thursday morning to find heavy smoke coming from the home in the 4600 block of Iris Street.
A neighbor across the street called 911, according to Montgomery County Fire Chief Steve Lohr.
A man standing outside said his mother was still inside.
Firefighters rescued the woman, who's in her 70s, on the home's second floor and took her to a local hospital with life-threatening injuries. She has since died.
Two firefighters are being treated for heat exhaustion.
The firefighters had to carry the woman out a window and down a ladder because the interior stairs to the home had burned through, Lohr says.
"This was a particularly difficult rescue," he says.
Fire officials say they believe the fire began in the home's basement.
"At some point this became a gas-fed fire. There is no indication it originated there."
Lohr says investigators are looking into whether the home's smoke detector was working.
The fire department has not assessed the amount of damage yet, and is expected to be on the scene most of the day.
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