A SigAlert was issued for the 405 Freeway at Wilmington Avenue earlier in the day, where the HOV and #1 lanes on the northbound and southbound sides were closed "until further notice," said the California Highway Patrol.
All lanes have since reopened, according to CHP.
Aerial footage from AIR7 showed a semitrailer with some of its wheels stuck in the center divider.
The CHP traffic incident website informed of several vehicles involved in the collision, which was reported shortly before 1 p.m.
It was not immediately clear if anyone was hurt in the collision. The cause of the crash is under investigation.
Traffic was slowing down in both directions as officers worked to clear the roadway.