Los Angeles school officials increased security at a local high school Tuesday morning, the day after a lunchtime brawl, involving at least 40 students, had occurred.

The Los Angeles Times reported that cellphone video captured the 20-minue escalation at Sylmar High School Monday. According to KNBC-TV, more than 12 officers were needed to control the situation.

"As the head of the most diverse school district in the nation, let me be very clear: We will not tolerate targeting or violence of any kind on our campuses," Los Angeles Unified School District Superintendent Michelle King said in a statement.

Principal James Lee said in an email to parents that the students involved in the fight will face “disciplinary action.” Lee also said that their parents had been notified.

It’s unclear what started the fight. However, students told KTLA that a race dispute over prom may have caused the melee. The Los Angeles Unified School District said police are investigating the incident.

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