A tanker truck overturned on the 210 Freeway in Sylmar late Monday night, prompting a closure of the westbound lanes that extended into Tuesday morning.
The crash occurred about 11:40 p.m. near Yarnell Street when the big rig drove into an embankment, according to the California Highway Patrol traffic incident log.
The CHP initially indicated the crash included multiple cars, but an official at the scene later concluded the big rig was the only vehicle involved.
The tanker was carrying some type of fluid, possibly tar, that spilled onto the freeway, CHP Officer Polizzi said.
The overturned truck and fluid leak prompted officials to shut down the entire westbound side of the freeway.
At one point, vehicles were exiting on the Roxford Street onramp.
Officials had hoped to reopen the freeway by 5 a.m., but two lanes and the transition road were still closed as of 10:30 a.m., when the SigAlert was extended for an additional two hours, according to the CHP log.
Check back for updates on this developing story.