Five firefighters suffered non-life-threatening injuries in the nine hours it took to put out the fire at The Villa on Prospect Street.
The three-alarm blaze broke out around 12:30 a.m. and was burning when the sun came up.
The elderly woman who was found unresponsive in one of the units later died, officials confirmed. Several portions of the building collapsed before the blaze was under control around 9 a.m.
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