North Hudson Regional Fire and Rescue (NHRFR) squads arrived on the scene soon after the fire started, said NHRFR fire director Jeff Welz. All of the buildings occupants were evacuated safely, said Welz.
Around 5 or 10 minutes after the firefighters' arrival, the fire reached the roof of the building, which holds apartments as well as a ground floor deli/market. Five minutes after that, the roof began to collapse, said Welz.
Three fire engines have raised their ladders and are currently shooting water onto the blaze from above. Helicopters are also hovering over the scene.
Before darkness fell, the smoke could be seen from 14th Street in Hoboken, and appeared to come from behind the old Yardley factory up the hill.
The fire's cause and point of origin have yet to be determined.
The fire was started on the fourth and top floor of the building, possibly in the south-east corner apartment, said Union City Chief of Police Brian Barrett.
"That's what we're hearing from the fire department," said Barrett. "We definitely got everyone out though. Thank God it wasn't in the middle of the night."
There were concerns that one person, a 93-year-old woman, had not been evacuated, but following a quick investigation it was discovered that she was with friends in an apartment across the street.
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