The crash happened around 5 a.m., when a vehicle rolled over and one person was killed. For a short time, all southbound lanes near the 105 Freeway interchange were closed. Traffic was diverted at Century Boulevard.
The carpool lane and two others were reopened a short time later, while three other lanes were closed for about two hours.
It was unclear what caused the crash.
The investigation is ongoing.
City News Service contributed to this report.