The wreck was first reported around 8 a.m. on the westbound 118 Freeway near the Tampa Avenue exit. The Tampa Avenue off-ramp and at least four lanes were shut down due to the wreck.
SIGALERT UPDATE IN PORTER RANCH: WB SR-118 AT TAMPA AVE - #2, 3, 4, 5 LANES, AND THE TAMPA AVE OFF-RAMP BLOCKED FOR AN ADDITIONAL HOUR DUE TO A COLLISION— CHP PIO - LA County (@CHPsouthern) October 19, 2018
The California Highway Patrol said the closures would last until at least 10:30 a.m.
The four injured individuals included one man who needed to be extricated from the semi-truck, the Los Angeles Fire Department said.
The conditions of those involved in the crash were not immediately known. The cause of the wreck has not yet been determined.