A multi-vehicle crash was backing up traffic on Highway 101 in San Luis Obispo Friday afternoon.
It happened at about 4:10 p.m. in the southbound lanes near the Los Osos Valley Road offramp.
The California Highway Patrol reports three to four vehicles involved.
No word on the extent of any injuries but CHP reports an ambulance was requested at the scene.
By 4:20 p.m., traffic was backed up to the Marsh Street exit.