Fire officials in Lowell are investigating the cause of a blaze which engulfed a multi-unit building in the city earlier Saturday.
Dozens of people were displaced as a result of the fire, officials said, which broke out on Westford Street in Lowell around 11 a.m.
One firefighter was injured as a result of the blaze, which at one point became so hot that firefighters had to exit the building and work to contain it from the outside.
The fire began in a business on the first floor, according to Lowell Fire Chief Phil Charron. The first floor is comprised of multiple businesses while the top two floors are comprised of apartments.
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"It very rapidly got into the apartments above, and then spread to the space between the third floor and the roof," Charron said.
Firefighters from at least six different communities in the area worked to extinguish the flames.
The cause of the fire remains under investigation.