SANTA CRUZ, Calif. (KRON) — A driver was killed after crashing into multiple trees along Empire Grade in the Santa Cruz mountains and the vehicle burst into flames.

The collision happened at 3 a.m. Sunday west of Felton, according to the California Highway Patrol.

“For an unknown reason, the Toyota veered off the roadway, collided into multiple trees, and subsequently caught fire,” the CHP wrote.

The Toyota Rav4 was fully engulfed in flames when emergency crews arrived on scene.

The cause of the deadly accident is under investigation. The CHP said its unknown whether drugs or alcohol were factors in causing the crash.

The driver’s identity was not released by the Santa Cruz County Sherriff’s coroner.