The three-vehicle pileup was reported about 4:45 a.m. near the Harbor Boulevard on-ramp, according to a California Highway Patrol incident log.
One person died at the scene. That individual was not immediately identified.
Three others were transported to hospitals with unspecified injuries.
Northbound traffic was backed up for miles as crews worked to clear the scene. Three lanes were later reopened.
The cause of the collision was under investigation.