All lanes reopened on southbound Interstate Highway 680 after two people were taken to the hospital Sunday evening, the California Highway Patrol reported.
One person was taken to the hospital with major injuries and another was transported with minor injuries, according to a CHP spokesman.
The CHP is still investigating what caused the crash.
Three lanes were closed on the highway at Jackson Avenue after a Sig-alert was issued at about 5 p.m. The alert was canceled at 5:20 p.m.
