By CBS3 Staff

KING OF PRUSSIA, Pa. (CBS) — Officials say 15 people, including six police officers and an EMT, were injured in a large blaze at an apartment building in King of Prussia late Wednesday night. The fire happened on the 200 block of West Byron Place in Upper Merion Township, around 10:20 p.m.

Fire officials tell Eyewitness News some residents had to jump from balconies in order to escape the flames, as the fire rose to two alarms.

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Chopper 3 was over the scene where massive flames could be seen shooting from the building’s roof.

Credit: CBS3

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Officials say the building was occupied and evacuated.

Authorities say four of those 15 people have been transported to a nearby hospital. Their conditions are not known at this time.

The Red Cross is working to relocate displaced residents. There is no word at this time how many residents have been displaced by the fire.

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There is no word on what started the fire.