An overturned big rig blocked lanes on the San Bernardino (10) Freeway in the Covina area early Wednesday, snarling traffic as the morning commute got underway.
The crash was reported at about 3:15 a.m. Wednesday on the eastbound freeway near the Barranca Street off-ramp.
No injuries were reported and it was not immediately clear what caused the rig to overturn.
Traffic was getting through in the carpool lane, but the five main lanes were blocked and the backup extended too Azusa Avenue.
A Sigalert remain in effect for several hours after the crash occurred.