Authorities say the victim suffered superficial cuts from knife on the third floor of the school in the 1500 block of West Washington Boulevard. The victim was taken to a local hospital for cuts on her arm.
LAPD confirmed that the suspect was either an older sister or relative of one of the girls who was involved in the altercation.
The suspect fled the campus following the attack and has not been located yet. She was described as being 18 or 19 years old, slim build, 5 feet 9 inches, with a three-dot tattoo under her left eye.
Parents were notified about the incident, and classes resumed at the school.