A two-alarm fire raged through an apartment complex in the Aspen Hill area Thursday and forced authorities to evacuate 50 familes from their homes, Montgomery County fire officials said.

Residents of the Manor Apartments noticed smoke inside their building in the 14300 block of Georgia Avenue and called 911 about 7 p.m., said Pete Piringer, a fire department spokesman. Responding firefighters found heavy smoke coming from the three-story building, which contained eight apartments.

Medics evaluated a 11-year-old boy at the scene, but no one was injured, Piringer said.

It took about 90 firefighters about 30 minutes to extinguish “the stubborn fire,” which was concealed in the walls and ceilings, Piringer said.

The fire was contained to the building where it started, but authorities were forced to shut off utilities to other buildings, so 50 families were displaced, Piringer said.

Investigators believe the fire was caused by electrical wires in the walls that overheated and sparked combustible material, which probably burned undetected for a period of time, Piringer said.

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