Firefighters responded to the 50 block of Patton Alley around 5:45 a.m., said Public Information Officer Dave March.
Units found heavy smoke and fire at the scene, and a resident was removed from the building before being treated by EMTs, authorities said.
March said the fire was brought under control just before 7 a.m. About an hour later, he announced that at least one person had died.
First responders were still on the scene as of 8 a.m. Authorities have not said yet what may have caused the fire.
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