MOSS LANDING, Calif. -

California Highway Patrol officers said Friday that the driver killed in a fatal crash on Highway 1 that also killed her passenger was only 15 years old.

The crash occurred between Jensen and Struve Road just after 7 a.m., and both lanes of the highway were closed until about 1:30 p.m.

Officers on scene said the teenage driver of a white Hyundai traveling northbound on Highway 1 swerved into oncoming traffic and crashed into a commercial truck, which was traveling in the opposite direction.

The driver and her 18-year-old female passenger, Santa Cruz residents, were both pronounced dead at the scene. The 15-year-old girl was ejected from the vehicle. Their names have not yet been released.

CHP officers say the cause of the collision is under investigation and it's unknown at this time whether drugs or alcohol were factors.

A car seat also was found in the roadway but officers believe it was empty.  After an extensive search they did not find a child.

As for the driver and passenger of the pickup truck, officers say they were not injured

Crews were headed to bring back power to the area after the truck slammed into a power pole as a result of the crash.