A California driving instructor and registered sex offender was busted for molesting a teen student during two driving lessons, local police said.

A 17-year-old girl reported on March 12 that 56-year-old Tom Lam had sexually assaulted her, the Los Angeles County Sheriff’s Department said in a statement. He was arrested at his home in the city of Montclair two days later, and booked for sexually assaulting a minor, police said.

The girl’s parents had paid Lam for six driving lessons with their daughter, they told police. While nothing happened during the first four, Lam violated the teen during the last two in the city of Rowland Heights this month, authorities said.

Special Victims Bureau officers soon discovered that this wasn’t Lam’s first offense. He is a registered sex offender — who targeted another driving student back in November 2014, according to police. He was charged with annoying or molesting a minor.

He was released on $140,000 bond on Sunday, and is due back in Pomona Court on April 8.

Police are looking to speak with other possible victims in the case — and are urging anyone with information to contact the Los Angeles County Sheriff’s Department’s Special Victims Bureau.