VIDEO: The Phoenix Fire Department is investigating a house fire that occurred in north Phoenix late Saturday night. At around 11:00 p.m., fire crews responded to a house fire near 19th Avenue and Union Hills Drive. According to Phoenix fire, when their crews arrived on the scene, they found the single-story structure engulfed in flames. Phoenix fire's strategy was later declared defensive meaning firefighters fought the fire from the exterior as nothing was viable on the interior due to the amount of fire.