Witnesses said the twin-engine plane was in "obvious distress" when it went down near San Luis Elementary School. The school was not in session at the time.
A dispatcher said the plane reportedly took off from nearby Oceanside Municipal Airport just before the crash.
Firefighters were dispatched to the scene near State Route 76 and North El Camino Real. It took them about 20 minutes to get the fire under control.
Associated Press and City News Service contributed to this story