The festival, which took place on Lindley Avenue near Hatteras Street, was hosted by St. Mary's Assyrian Church.
Children ranging in age from 3 to 10 years old got trapped when the two-story-tall slide collapsed on Saturday.
Firefighters said a group of older kids had overloaded the slide.
Four children went to the hospital with minor injuries, according to investigators.
The Los Angeles Fire Department allowed the slide to be re-inflated for use, saying it did not malfunction.