The crash resulted in heavy delays in the area. All traffic was diverted off at 5th Street for several hours.
The crash was reported shortly after 4 a.m. when a pedestrian crossed onto the freeway and was struck by a blue and white semi with a trailer attached, according to the California Highway Patrol. The deceased individual was not immediately identified.
The investigation is ongoing. The CHP urged drivers to expect delays and use alternate routes during the shutdown.
All lanes were reopened as of 8 a.m., the Highway Patrol said.
The cause of the collision is under investigation.