The fire broke out around 7:15 a.m. in a two-story home in the 2700-block of S. Lowe Avenue.
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Chicago firefighters were battling thick smoke and flames when they were caught in what's known as a "flashover," fire officials said.
"All the content in its infrastructure catches fire all at once, and everything burns and it gives you seconds to get out of the fire," said District Chief Steven Clay, Chicago Fire Department.
Officials said one firefighter was forced to jump to another roof. In all, seven firefighters were injured.
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CFD spokesman Larry Langford said the firefighters suffered from some steam burns and falls, but will be fine.
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It was not immediately clear how the fire began.
A man was able to safely escape before the fire department got there. He lived there with four dogs, fire officials said.
Even as the scene calmed down, many in the neighborhood were stuck in the dark. ComEd said the fire department asked the utility to cut power to 422 customers.
Among them was Reno Castillo, who said his home is three blocks away.
"We run electricity for the water heater. We got nothing right now," Castillo said. "It's freezing in the house. Temperature goes down real fast in somebody's house, you know."
A ComEd spokesperson said power was restored to all customers shortly after 6 p.m.
Fire officials continue to investigate the cause of the fire.