The flames broke out around 7:45 a.m. at the building on Washington Street in Bloomfield, starting at a florist and spreading to other stores and offices.
Fire departments from Newark, Montclair, Clifton, Belleville, Nutley, East Orange, West Orange, West Caldwell, Caldwell and Irvington are on the scene assisting the Bloomfield Fire Department.
"Right now, they're conducting an exterior operation because the fire was burning throughout the floors and walls of the building, and it became too dangerous to operate inside," Bloomfield Fire Chief Lou Venezia said. "Once we knock down the bulk of the fire, we'll go back in and mop it up, but there's pockets of fires that you just have to put out."
At this time, no injuries have been reported, but the two-story building houses 10 businesses that were all damaged.
Officials said there are closures on Glenwood Avenue, Washington Street, Bloomfield Avenue, Liberty Street, Conger Street and Lackawanna Plaza.
The cause of the fire is under investigation, but at this point, it is not believed to be suspicious.
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