A Livermore man was charged Monday with sexually assaulting a 60-year-old woman on a bus bench in San Francisco, authorities said.

Fidel A. Padilla, 41, was held without bail when he appeared in San Francisco County court to face one count of rape of an unconscious person in connection with the Dec. 16 attack.

According to San Francisco police, several witnesses on a bus passing by saw the attack underway about 6:30 p.m. in the 900 block of Market Street.

One bus passenger yelled at the assailant to stop. Several passengers then got off the bus to help the victim and contact police.

The assailant was gone, but police obtained video surveillance footage that captured images of a possible suspect. The images were passed to police officers on the beat.

Nearly seven hours later, officers patrolling in the 300 block of Golden Gate Avenue spotted Padilla, who matched the attacker’s description, police said.

Padilla, who was detained, was positively identified as the alleged assailant and taken into custody.

Alameda County Superior Court records show Padilla has been in and out of court and jail since 2002 for crimes including assault, being under the influence of drugs, possession of drugs, theft, vandalism, battery, residential burglary, receiving stolen property and car burglary. Last year, a judge ordered him to involuntarily take anti-psychotic medications.

Police released no information on the victim’s condition.