From trapeze artists to elephants standing on hind legs, gravity-defying performers draw big audiences to the circus. But last weekend, during a Ringling Bros. show in Rhode Island, gravity got the best of eight acrobats hanging by their hair, and they plummeted to the ground.

The “human chandelier” fell 25 to 40 feet in front of 3,900 spectators after a clamp snapped. Some sustained broken bones, and two acrobats remained in critical condition on Monday morning. None of the injuries appears life-threatening, however, according to Stephen Payne, spokesman for Feld Entertainment, Ringling Bros.’ parent company.

“We want to make sure all of our performers are safe,” Payne told the Associated Press. “An accident like this is unprecedented involving this number of performers.”

The incident is the latest controversy to spotlight the famous traveling circus. One of its aerial performers died in 2004 when a scarf broke while she was 30 feet off the ground.

Recently, Payne spoke out against Los Angeles’ decision to ban the use of bullhooks, baseball bats, and other pain-inflicting objects circus trainers use to control elephants. According to Payne, the decision was “unsupported by any evidence or proof of elephant abuse in Los Angeles,” and “it will deprive families of the right to take their children to see live animals at the circus.”

Apart from receiving abuse, animals also suffer from accidents. In a Ringling Bros. exposé titled “The Cruelest Show on Earth,” Mother Jones’ Deborah Nelson detailed a fatal accident in 2004 involving an eight-month-old elephant. It had to be euthanized after breaking two legs during a training exercise.

While performers know the risks of the business, animals do not. Like zoos, the circus is a centuries-old form of entertainment. Yet unlike the former, the big tent stands not for conservation but for spectacle (though this is also debatable in the case of zoos).

Ringling Bros. mostly remains true to its traditions, but some of its competitors have revamped their shows. Many, such as the Big Apple Circus, only work with domesticated animals. Cirque du Soleil’s big tent doesn’t feature animals at all. Perhaps some of the circus’ stunts need to be redesigned for the sake of the human performers too.