The crash was reported around 10 p.m. Monday near the Avalon Boulevard exit, according to the California Highway Patrol's traffic log.
The traffic log indicates two vehicles collided, and while traffic was stopped, a woman got out of her car and was struck and killed by an oncoming vehicle.
Deadly crash shuts down southbound 405 Freeway in Carson
The woman has not been identified. At least one other person was transported in unknown condition, according to the CHP.
Further details on what led up to the crash were not immediately available.
All southbound lanes were closed until around 4 a.m. when crews cleared the scene.