The California Highway Patrol responded to a call of the fiery semi-truck crash at about 3 a.m. on the 5 North near Rosecrans Avenue, authorities said.
CHP officials said the jack-knifed big rig was blocking all lanes near the Rosecrans Avenue ramp. No injuries were reported, according to authorities.
All lanes were expected to be shut down until further notice, the CHP said.
SIGALERT UPDATE NORWALK: NB I-5 AT ROSECRANS AVE, ALL LANES BLOCKED UNTIL FURTHER NOTICE- TRAFFIC DIVERTED OFF AT CARMENITA
— CHP Southern Div. (@CHPsouthern) May 21, 2016
It was not immediately clear what caused the vehicles to crash. The investigation was ongoing.