Updated October 29, 2021 at 5:55 PM ET

At a press briefing Wednesday, District Attorney for Santa Fe County, Mary Carmack-Altwies, said it's too early for any charges in the investigation into the Rust film shooting that left cinematographer Halyna Hutchins dead, but she added that "no one has been ruled out at this point."

She cautioned against jumping to conclusions about the case. Interviews are ongoing and investigators are sending evidence found on set to the FBI crime lab in Quantico, Virginia.

"If the facts and evidence and law support charges, then I will initiate prosecution at that time," Carmack-Altwies said. "I am a prosecutor that was elected in part because I do not make rash decisions and I do not rush to judgment."

Actor/producer Alec Baldwin, Rust assistant director David Halls and the film's armorer Hannah Gutierrez Reed — the three people on set known to have handled the gun — have all been cooperating with the investigation, Santa Fe County Sheriff Adan Mendoza said.

Mendoza also said about 500 rounds of ammunition were found on set: a mix of blanks, dummy rounds and what investigators believe to be additional live rounds.

Baldwin was rehearsing a scene for 'Rust'

Last Thursday, Baldwin was sitting in pew in a small church on the set, rehearsing a scene for Rust, a Western film set in the 1880's. According to affidavits for search warrants released by the Santa Fe County Sheriff's Office, Baldwin was rehearsing how he would draw a revolver and point it at the camera. The gun fired, killing cinematographer Halyna Hutchins and injuring director Joel Souza.

Souza told detectives he had been looking over Hutchins' shoulder when he heard "what sounded like a whip and then loud pop." Camera operator Reid Russell, who had been standing next to them, told investigators after the gun went off, Hutchins "said she couldn't feel her legs" and that medics treated her as she was bleeding on the floor.

According to one of the search warrants, the film's assistant director David Halls had taken the gun off a prop cart outside of the church and handed Baldwin the gun, after yelling out "cold gun"-- indicating he believed it wasn't dangerous. In a new affidavit released Wednesday, Halls shared with authorities that he hadn't thoroughly checked each of the rounds of ammunition, as he said should have.

At Wednesday's press briefing, Santa Fe Sheriff Adan Mendoza said the gun was a Colt .45 revolver. A projectile was later recovered from film director Joel Souza's shoulder. It's "apparently the same round" that killed Hutchins, Santa Fe Sheriff Mendoza said, though further investigation is needed to confirm that.

On set, script supervisor Mamie Mitchell called 911 for help. "We had two people accidentally shot on a movie set by a prop gun," she told the emergency dispatcher, in a recording from the Santa Fe County Regional Emergency Communications Center. "We were rehearsing and it went off, and I ran out, we all ran out."

The dispatcher asked if the gun was loaded with a real bullet.

"I cannot tell you. We have two injuries," Mitchell replied. "And this ******* [assistant director] that yelled at me at lunch, asking about revisions... He's supposed to check the guns. He's responsible for what happens on the set."

Mitchell is now being represented by attorney Gloria Allred, who said in a statement that the script supervisor had been standing close to Hutchins and Souza when the gun went off. Allred says her office is doing its own investigation of the incident.

During Rust, Halls worked with armorer Hannah Gutierrez Reed. According to an affidavit, Reed prepared three guns and placed them on a cart outside the church where the scene was being rehearsed. After the shooting, she was given the gun and removed a spent casing before handing it to the deputies, according to the documents.

Reed hired attorneys in New Mexico, Jason Bowles and Robert Gorence. They issued a statement on her behalf that reads, in part: "Safety is Hannah's number one priority on set. Ultimately this set would never have been compromised if live ammo were not introduced. Hannah has no idea where the live rounds came from. Hannah and the prop master gained control over the guns and she never witnessed anyone shoot live rounds with these guns and nor would she permit that. They were locked up every night and at lunch and there's no way a single one of them was unaccounted for or being shot by crew members. Hannah still, to this day, has never had an accidental discharge. The first one on this set was the prop master and the second was a stunt man after Hannah informed him his gun was hot with blanks.

Hannah was hired on two positions on this film, which made it extremely difficult to focus on her job as an armorer. She fought for training, days to maintain weapons, and proper time to prepare for gunfire but ultimately was overruled by production and her department. The whole production set became unsafe due to various factors, including lack of safety meetings. This was not the fault of Hannah."

On a podcast last month called "Voices of the West," Reed talked about her first job as lead armorer earlier this year for the upcoming Western film The Old Way. "I almost didn't take the job because I didn't feel ready," she said. She learned about handling guns from her father, Thell Reed, a long-time Hollywood armorer.

'Rust' crew members had walked off the set earlier that day

A number of Rust crew members had walked off the set earlier in the day, hours before the shooting. They complained about working conditions and housing during the low budget production. The union IATSE's local 480 in New Mexico released a statement that read, in part: "We have been greatly disturbed by media reports that the producers employed non-union persons in craft positions and worse, used them to replace skilled union members who were protesting their working conditions. That is inexcusable."

It's too soon to tell how this may or may not affect the upcoming vote to ratify a new contract between the International Alliance of Theatrical Stage Employees and the Alliance of Motion Picture and Television Producers. Days before the shooting, the two sides reached a tentative deal over some working conditions and pay. Union members, including cinematographers, editors, hair and makeup artists, costume designers and more had voted overwhelmingly to strike if a deal wasn't reached when it was. Details of that deal and this shooting incident have prompted conversations about gun safety on film sets, more worker protections for crew members and more.

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