The two-alarm blaze was reported around 11 p.m., Wednesday, Oct. 5 at the apartment building in the 2370 block of Glenmont Circle near Georgia Avenue, according to Montgomery County Fire and Rescue.
An exterior couch fire in the three-story garden apartment reportedly rapidly grew and spread to the utility closet and common HVAC causeway throughout the building, extending into the interior of the building, authorities say.
Firefighters responded to the scene to contain the blaze, which they say caused around $600,000 in damages.
Authorities say that 16 adults and five children were displaced as a result of the fire.
The cause of the fire is still under investigation.
Click here to follow Daily Voice Gaithersburg and receive free news updates.