Officials say the fire broke out on the sixth floor of the Clay Avenue apartment building before 8:30 a.m. and spread to the cockloft.
Crews were able to get the fire under control at 10:12 a.m.
One firefighter was seriously injured but was said to be conscious and alert.
Another firefighter and a civilian were taken to the hospital with non-life threatening injuries, while a second civilian was treated at the scene.
The Red Cross has registered40households, including 94 adults and 21 children,for emergency assistance, including temporary lodging, financial assistance and disaster health services.
The cause of the fire is under investigation.
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