An hourlong Sigalert was issued just after 5 a.m. with the freeway closed at Lark Ellen Avenue. The freeway reopened just after 6 a.m.
An off-duty LAPD officer was reportedly involved in the crash.
It was not immediately known whether the off-duty officer was injured, but there were reports of a person trapped at one point.
Video from AIR7 showed traffic stalled for several miles.
The cause of the crash was not immediately known.