A big rig launched off a transition road in the San Fernando Valley area, bursting through a concrete barrier and landing on lanes below.
Authorities said the driver was conscious after the wreck, which occurred just before 10 a.m. at the 5 and 118 Freeway.
The northbound 5 Freeway to the westbound 118 was closed, including the Paxton on ramp. The westbound 118 to the northbound 5 was also closed.
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It wasn't immediately clear when lanes would reopen.
The driver was taken to the hospital.
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