Crews were dispatched around 10:53 a.m. to a fire on University Drive. The first units arrived within minutes and reported heavy fire conditions.
Firefighters quickly made a rescue from a first-floor window. Four other occupants escaped on their own, including one person who jumped from a window, officials said.
Wind made firefighting conditions more difficult, and a third alarm was called about 15 minutes into the response. The fire was brought under control roughly an hour after crews arrived.
Officials said seven people were injured. Five were taken to Duke University Hospital for treatment, including one firefighter who suffered non-life-threatening injuries.
Firefighters also rescued a dog trapped inside one of the apartments.
The cause of the fire remains under investigation. Officials said the investigation is being challenged by severe damage and structural instability at the scene.
In total, 33 units and about 75 firefighters from the Durham Fire Department responded. Several other agencies assisted.
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