UNION CITY, N.J. (CBSNewYork/AP) — Firefighters are still on the scene of a huge 3-alarm blaze that ripped through a New Jersey apartment building Monday afternoon.

Investigators are waiting for things to cool down before they start looking for what started the fire in the four-story multi-family building on Bergenline Avenue in Union City.

More than 20 apartments and at least two businesses on the first floor were destroyed.

No one was injured, but dozens of residents were displaced in the fire.

“We lost everything,” said resident Alexander Cruz. “In 30 minutes, one hour — you’ve lost everything.”

Cruz, his wife, 4-year-old daughter and 2-week-old son joined close nearly 100 other people inside a school gymnasium Monday night waiting to find out where they would be relocated.

“We will help them relocate back here or within Union City,” said Mayor Brian Stack.

Stack said he plans to hold a fundraiser for the displaced families in the next few days.

There’s still no word on exactly what sparked the blaze, but North Hudson Regional Fire Chief Frank Montagne told The Jersey Journal the fire apparently began on the fourth floor and was fueled by a tar roof.

The Red Cross is working to relocate residents.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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