All lanes were reopened on the 71 Freeway in Chino Hills on Wednesday afternoon following a fatal crash.
The crash was reported around 8:15 a.m., forcing a closure of all lanes on the southbound 71 Freeway, according to the California Highway Patrol.
At least two people were killed and five others were injured, authorities said.
Video from NewsChopper4 showed a box truck on its side on top of a vehicle.
All lanes reopened around 1 p.m.