A jackknifed big rig blocked traffic on Highway 101 in Carpinteria on Monday.
It happened at about 1:30 p.m. in the southbound lanes at Santa Claus Lane.
Caltrans and the California Highway Patrol said both southbound lanes were blocked. It was unknown when the truck would be cleared from the highway but authorities said drivers should expect delays during the evening commute.
Traffic was being diverted to Via Real.