The inmate, identified as 31-year-old Jonathan Alfaro, walked away from a work detail at the Pre-Trial Detention Facility at 800 S. Victoria Avenue around 7 p.m. Thursday, according to the Sheriff's Department.
Sheriff's deputies with flashlights were seen combing dark grassy areas near the jail and a helicopter was searching from overhead.
Alfaro is a burglary suspect and authorities say he is not considered a danger to the public. But anyone who spots him is asked not to approach him, but instead call 911 immediately or the department at (805)654-9511.
He was assigned as a kitchen worker and was last seen on the loading dock before walking away from the grounds.
The department says a screening process assigns inmates who are in custody for non-violent crimes to work assignment areas that may offer limited security. Such inmates are asked to sign contracts that are known as escape clauses.
Alfaro is described as a Hispanic male, standing about 5 feet 4 inches tall, weighing around 140 pounds. He was last seen wearing jail clothing - blue jeans and an orange T-shirt. He has short black hair and a black beard and mustache.