NEWPORT BEACH, Calif. – A California tutor pleaded not guilty this week to five felonies for allegedly hacking into Corona del Mar High School’s computer system to change the grades of at least three students.

Timothy Lance Lai

Timothy Lance Lai, 29, was arrested earlier this month at Los Angeles International Airport upon returning to California after fleeing the country amid allegations he helped several students cheat.

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Police allege Lai, a private tutor, broke into the high school last year to install a USB device he used to record teachers’ keystrokes, information he later used to hack into the school computer system and change the grades of three students in two different classes, according to media reports.

The Orange County Register reports Lai was a tutor at several schools, and initial reports estimated as many as 150 students may have been involved. School officials expelled 11 students believed to be involved in the broader grade-changing scheme, but the charges against Lai are for only three students.

A teacher of one of the students noticed the changed grades and notified school administrators, who then called in the Newport Beach Police Department, and the cops found a USB device on a third teacher’s computer, OCWeekly.com reports.

Lai is charged with one felony for second degree commercial burglary, and four counts of computer fraud. If convicted, he could face up to five years and eight months in prison.

“‘We don’t know the number (of students affected) because he was tutoring at Mater Dei’ and elsewhere,” Newport-Mesa school board member Katrina Foley told OC Weekly.

“There’s probably hundreds of kids affected by this individual,” she said.

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Lai was originally busted when a student involved in the scandal called Lai from the Newport Beach Police Department in a recorded conversation, and the tutor admitted to the hacking. Police searched his home and vehicle, but Lai fled the country before police could interview him, the Register reports.

The recorded conversation was on December 18, 2013, and Lai was arrested at the airport October 6, 2014.

School officials told the media Lai, a high-level math and science tutor, was employed mostly by wealthy parents, and often befriended students, hanging out with them beyond their study sessions.

School leaders dodged questions about the cheating scandal for months, but Jane Garland, the administrator in charge of discipline, spoke out earlier this year saying school officials stalled for months before going to police or notifying parents, OC Weekly reports.

Garland was promoted in August 2013 to implement the district’s “restorative justice” approach to student discipline, which seeks to keep student in school rather than suspend or expel them for bad behavior, the Register reports.

Garland told the Register in January the district would apply restorative justice to students involved in the hacking scandal, and she set up “stipulated expulsions” as punishment, which allowed the students to transfer to other schools in the district with a sealed record.

Garland then highlighted the fact that some students were removed from the list for punishment, and received preferential treatment, and pointed directly to school principal Kathy Scott, whom she said knew about the scandal for months before contacting police.

Garland resigned from the district in February, OC Weekly reports.