Thirty child actors – some as young as 4 years old – were put at risk during the filming of a battle scene last month on the Georgia set of Lionsgate's "Allegiant." In the chaotic scene during production of the third film in the "Divergent" series, child actors scrambled through a gauntlet of more than 100 untrained adult extras swinging metal clubs, axes and machetes. No one was seriously injured during the first day’s shoot, but quick action by a witness – and the intervention of representatives from IATSE Local 479 in Atlanta – might have averted a disaster on the second day.

Since the death of Sarah Jones on the set of Midnight Rider last year, the industry’s catchphrase has become, “If you see something, say something.” The witness, who asked to remain anonymous, knew Jones and took that phrase to heart.

On the morning of June 17, more than 130 extras began arriving at an old abandoned mill in rural northwest Georgia to begin the day’s work. They weren’t there long before the prop masters began handing out the heavy metal weapons – including axes, machetes, scythes, maces, steel pipes, hammers, heavy farm tools and pieces of steel rebar – that most of them would be wielding in the scene. They’d be battling soldiers who’d come to their village of genetically damaged outcasts to take away their children.

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As the fight scene unfolded, the children fled in all directions, chased by soldiers. “I had to do a double take when the prop master passed out the weapons to the extras,” the witness wrote in an email to the film’s safety consultant. “Concerned, I went around and handled the weapons for myself and saw that they were steel and aluminum, with bladed edges, and some were quite sharp.”

In the film, the settlement under siege is called The Fringe, and the villagers are fierce warriors who fight with whatever weapons they can muster. “Most of the Fringe adults were given prop weapons for action scenes in which they were running around panicked as their children were kidnapped, with soldiers chasing them,” the witness wrote. “The children were also running through the melee, and as the scene progressed they were breaking free and running in all directions on their own as the Fringe adults tried to stop the soldiers.”

Shocked by what he was seeing, the witness spoke discreetly with several members of the crew. “Everyone seemed to know it was wrong, but no one was willing to speak up,” he told Deadline. “To me, it seems that saving money – the expense of rubber props – took priority over safety. This particularly upset me because small children were involved. I personally saw four people trip and fall just because of the footing on the set, and several people were given medical care for heat exhaustion, which can cause fainting – and falling on these weapons is just as dangerous as swinging them into someone else during the chaotic scene.”

Filming wrapped for the day, but they’d be back the next day to do it all over again.

The next morning, after a sleepless night, the witness called the SAG-AFTRA safety hotline to report the dangerous environment for the child actors, but got only a recording. Then he called SAG-AFTRA’s stunt and safety office in Los Angeles, but it wasn’t open yet. He then reached out to a SAG-AFTRA rep in Georgia, again getting a recording, and the guild’s Southern regional office in Miami, but got nowhere. “Dissatisfied, I called IATSE Local 479, who blew up when they heard what was going on.”

Ten minutes after that call, as the extras and children were preparing to shoot another scene, the prop masters came onto the set and rounded up all the metal weapons and replaced them with a few rubber replicas. “I felt immense relief that I wouldn’t see some child lose an eye or some extra get cut wide open by a blade as they ran around,” the witness said. “Local 479 made that set safe immediately.”

“It was brought to our attention, and it was handled immediately,” said a Local 479 official. “Safety is of the utmost importance to us. Any calls regarding safety issues are handled expeditiously.”

The film’s safety consult declined to discuss the matter with Deadline, but in an email to the witness, he wrote: “Thank you for bringing this to my attention. I do not and will not take this lightly. As you are well aware of, these weapons are completely unsatisfactory for the type of action that you have described. I will bring this to the attention of all key personnel involved with this production as well as Lionsgate executive staff. Thank you for your willingness to express yourself and others and I will continue to do everything I can to make our industry safer, injury and fatality free.”

The film’s producers did not respond to requests for an interview, however, a Lionsgate spokesman told Deadline: “We take safety issues very seriously, and we are currently investigating this.”