Chopper 7 was over the building fire near 77th Street and Peoria Street on Wednesday around 9 a.m.
The fire started at a vacant building, Chicago fire officials said. At some point the building collapsed.
The flames spread to an apartment building, however firefighters got it under control quickly.
A man was taken to a hospital to be treated for injuries related to smoke.
Two adults and two children were displaced.
It's unknown how the fire started.
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