The California Highway Patrol has not determined the cause of the accident that snarled traffic on the eastbound 210 Freeway on Wednesday morning.
Sgt. Mike Dulong of the Baldwin Park CHP office said field officers are still investigating the accident in which a Jeep overturned in the middle lanes of the freeway, trapping the injured driver inside.
Dulong added he does not know the status of the driver, who was taken to an undisclosed local hospital.
CHP reports show the accident occurred just before 8 a.m. near the Huntington Drive exit.
All eastbound lanes of the freeway—except the carpool lane—remained closed as CHP officers and firefighters rendered aid to the Jeep's driver and cleared the wreckage.