The police investigation into a fatal shooting with a prop gun fired by actor Alec Baldwin on a film set was focusing Saturday on the specialist in charge of the weapon and the assistant director who handed it to Baldwin.

Ukraine-born cinematographer Halyna Hutchins, 42, was struck in the chest and died shortly after the incident Thursday in New Mexico, while director Joel Souza, 48, who was standing behind her, was wounded and hospitalized, then released.

Police interviewed Baldwin, who willingly cooperated, but have pressed no charges.

The gun, which was supposed to be loaded with a blank charge, instead had a live round, according to the affidavit submitted by the sheriff's office to obtain a search warrant, local media reported.

The affidavit said that Assistant Director Dave Halls, identified as the man who handed the gun to Baldwin, called out "cold gun" as he did so -- industry talk to indicate the weapon had only a blank charge.

Police are focusing intently on the exact sequence of events that allowed the live round to be introduced to the film set of 19th-century Western "Rust."

A 911 call to police immediately after the shooting conveyed the shock and anger felt on the set.

"We've had two people accidentally shot by a prop gun; we need help immediately," the caller tells a police dispatcher.

Actor Alec Baldwin, who fired a prop gun that killed a director of photography on the set of a Western he was filming, is seen here in 2019
Actor Alec Baldwin, who fired a prop gun that killed a director of photography on the set of a Western he was filming, is seen here in 2019 AFP / Angela Weiss

"Was it loaded with a real bullet?" the dispatcher asks.

"I don't -- I can't tell you that," the caller replies. "And this (expletive) AD that yelled at me at lunch ... this mother (expletive) - he's supposed to check the guns, he's responsible for what happens on the set."

Baldwin has said he was heartbroken and was cooperating fully with the inquiry into "how this tragedy occurred." He retweeted a story from trade journal Variety headlined "Alec Baldwin Was Told Prop Gun Was Safe Before Fatal Shooting, Affidavit Says."

The gun used, and two others, were provided by the film's weapons master, or armorer, who has been identified as 24-year-old Hannah Gutierrez-Reed, the daughter of longtime film-industry armorer Thell Reed.

In a September podcast, the young Gutierrez-Reed said she had some trepidation about taking on the role of lead armorer for the first time for the previous movie she worked on, "The Old Way."

"I was really nervous about it at first and I almost didn't take the job 'cause I wasn't sure if I was ready," she said on the "Voices of the West" podcast, before adding, "But doing it, like, it went really smoothly."

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