Caltrans has issued an alert for motorists driving Highway 101 south of San Luis Obispo because of a car that ran off the roadway and into a ditch.
At 4:13 p.m., a car was reported into a ditch just north of where South Higuera Street goes under the highway at the city's southern end.
According to a CHP dispatch website, one person in the vehicle was able to get out, but another person remained trapped.
The car, a Nissan Maxima, was traveling north on the freeway when it ran into the ravine and rolled. A dog was thrown out of the auto.
Traffic is backed up in both directions at the accident scene.