STUDIO CITY (CBS) — A big-rig hauling sand smashed through a divider on the Ventura (101) Freeway, seriously injuring one person and blocking traffic for miles during the morning commute.

The accident happened shortly after 6 a.m. when an eastbound big rig struck a van, which burst into flames near Laurel Canyon Blvd. The rig punched through concrete center divider and jackknifed, causing a secondary collision.

Officials said that van driver suffered first-to third-degree burns on his legs and arms.

The CHP says the driver of the big rig was initially suspected of drunken driving. They say he may have been dazed by the accident, and the officer in charge on the investigation apparently mistook him for being intoxicated. He was later released without being booked for a crime after passing a sobriety test.

It took authorities until about 10 a.m. to reopen all lanes.

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