The trailer overturned around 2:30 a.m. in Pomona after trying to avoid another car that crashed. The westbound 10 Freeway between Indian Hill Boulevard and Towne Avenue was shut down, and a traffic alert was issued until 6 a.m.
A driver of a sedan hit the center divider and lost control, before the tractor-trailer hit the car. The driver was arrested on suspicion of driving under the influence. Authorities said they received several calls of a person driving erratically.
The driver of the sedan suffered minor injuries.
Crews cleaned up a swathe of rocks covering the road with brooms, shovels and street sweepers.
