Initial reports of an "active shooter" after the blaze prompted a massive police response.
The Los Angeles Police Department was on citywide tactical alert after firefighters extinguished the blaze at a two-story home in the 15400 block of Orchard Avenue.
There were no immediate reports of injuries in the fire or the shooting.
According to the LAPD, the suspect was barricaded inside of a home. Police and sheriff's deputies evacuated the area as the standoff continued.
DEVELOPING: More details will be added to this report as they become available.