An early morning fire that broke out in the rear garage of a private residence in the city’s 15th District has been determined to be an act of arson, according to fire officials. The blaze occurred at approximately 4:43 a.m. Wednesday on the 4100 block of Decatur Street. Multiple 911 calls were received, and firefighters from Ladder 20 and Engine 36 responded to the scene. The fire was brought under control by 5:29 a.m. The fire has displaced residents from two homes on the block. No injuries have been reported in connection with the incident. The Philadelphia Fire Marshal’s office has classified the fire as arson. The scene remains secured as investigators continue their work. No arrests have been made, and the investigation is ongoing.