The fire broke out around 7:38 p.m. on Tuesday, March 11, in the 45800 block of Peach Oak Terrace in Sterling, prompting multiple 9-1-1 calls from concerned neighbors.
When firefighters arrived, flames were already ripping through the front of the home.
Crews from Loudoun County, Fairfax County, and the Metropolitan Washington Airports Authority launched an aggressive attack, knocking down most of the blaze within 10 minutes.
Fire investigators determined the cause to be a mechanical malfunction in the engine compartment of a vehicle parked in the garage.
The fire caused an estimated $650,000 in damage but no injuries were reported, officials said.
Two adults and a child were displaced and are receiving assistance from the American Red Cross. Smoke alarms inside the home were working properly and alerted the occupants, authorities said.
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