A firefighter was injured and six adults were displaced by a four-alarm house fire in Somerville, Massachusetts, Saturday afternoon.
Workers were renovating a vacant home on Morrison Avenue when the fire started, according to Somerville Fire Chief Charles Breen.
"When we arrived at the house that was under renovation, [it] was fully engulfed," Breen said. "As you can see, it collapsed. It spread to houses on both sides."
As the wood-frame house was under renovation, walls, ceilings and windows had been removed. This allowed the fire to spread rapidly through the building, according to Breen.
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The fire heavily damaged two other homes. Three additional houses suffered minor damage.
The fire was so hot that it even burnt the siding of a house across the street.
"With a city that is highly congested like this, we need to get ahead of it or we could lose an entire city block," Breen said.
A witness's video shows large flames and black smoke shooting out of the home.
Neighbors stared at the fire in disbelief as flames shot into the air and black smoke could be seen from across town.
"The flames were just unbelievable," said Somerville resident Maureen Norman.
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Crews were digging to turn off the gas in the area Saturday afternoon. The State Fire Marshal's Office was at the scene as part of the investigation.
By evening, crews worked to demolish what was left of the house.
It is unclear what caused the fire.