Thirty-five people who were stung were transported to hospitals for minor injuries. Witnesses said one person was stung about 13 times.
Los Angeles County fire officials responded to the school at around 1 p.m. following a report that multiple students were stung by a swarm of bees. Seven ambulances were sent to the scene.
Emergency personnel evaluated up to 40 patients, and a classroom was locked down due to the incident while students fled indoors for their safety.
Authorities said the incident unfolded when someone threw an apple during lunchtime at a beehive that had formed at the school over the summer.
A beekeeper who was also called to help respond to the situation said the type of bees involved were more aggressive than the average honeybee.
Beekeeper Steven Melton said rating their aggression on a scale of 0-10, these bees would be about an 8.
"This looks like your generic honeybee, but they have a very high aggressive tendency," Melton said.