FALLBROOK, Calif. — A driver and a passenger were killed in a rollover crash in the Fallbrook area Sunday, said California Highway Patrol.

The incident occurred around 1:33 a.m. when a 32-year-old man was driving a Lexus NX350 in the southbound lanes of Interstate 15. For reasons still under investigation, CHP says the Lexus veered off the roadway to the right and overturned.

According to officials, both the driver of the Lexus and a passenger — a 28-year-old woman — were pronounced dead at the scene.

It is not yet known if alcohol and/or drugs contributed to the cause of this collision. The identity of both the driver and passenger will be released through the San Diego County Medical Examiner’s Office.

The investigation is ongoing. CHP is asking anyone who has information or may have witnessed this incident to contact the Oceanside Area CHP office at (760) 643-3400.