PFD was called to the 5200 block of C Street near Rising Sun Avenue in Olney around 1:20 a.m., a spokesperson said.
First responders arrived to find heavy fire on the first floor of a two-story home with multiple people trapped inside, according to authorities. The fire reached "all-hands" status and more than 60 firefighters eventually responded to the scene, the department said.
Four people were treated for injuries at the scene and then taken to area hospitals, officials said. The blaze was placed under control by 1:52 a.m.
The Fire Marshall's Office is investigating the cause, the spokesperson added.
More than 20 Philadelphians were displaced by house fires between Wednesday and Thursday, according to PFD. All city residents are reminded to call 311 to have free smoke alarms installed.
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