Sheriff's deputies are advising residents to be on the lookout for a San Francisco boy who left a juvenile rehabilitation center in San Mateo County without permission early Saturday morning. The boy left Log Cabin Ranch, located at 500 Log Cabin Ranch Road in La Honda, without permission shortly after 1 a.m., the San Mateo County Sheriff's Office said. The boy was receiving rehabilitation at the minimum-security detention facility for a misdemeanor crime, police said. Log Cabin Ranch is a court-ordered school in the San Francisco Unified School District, and is run by the San Francisco Juvenile Probation Department. The boy is enrolled in the facility's yearlong program for San Francisco's most at-risk youth. He is Hispanic, stands 5 feet 9 inches tall and weighs 200 pounds, and has black hair and brown eyes. Deputies said he was last seen walking in the area wearing a dark T-shirt and khaki pants. Anyone who sees the boy or a suspicious person in the area, especially if they are trying to flag down a vehicle, should call 911 immediately.