The prop gun fired by Alec Baldwin contained a live round, prop masters union says

• The prop gun Alec Baldwin fired on the "Rust" set contained a "live round," the IATSE said.
• The single live round hit both Halyna Hutchins and director Joel Souza, the union added.

The prop gun actor Alec Baldwin fired on the set of the film "Rust" on Thursday, killing director of photography Halyna Hutchins and injuring director Joel Souza, contained a "live round," a union covering prop masters told its members.

The email from the International Alliance of Theatrical Stage Employees Local 44, seen by IndieWire, called the incident an "accidental weapons discharge."

"A live single round was accidentally fired on set by the principal actor, hitting both the Director of Photography, Local 600 member Halyna Hutchins, and Director Joel Souza," the email said. "Local 44 has confirmed that the Props, Set Decoration, Special Effects, and Construction Departments were staffed by New Mexico crew members. There were no Local 44 members on the call sheet."

A source in the union told the Los Angeles Times that it remains unclear what type of projectile was in the gun, and that "live round" in the film industry refers to anything loaded into a gun, including blanks.

Sheriff's deputies were dispatched to the film's set at Bonanza Creek Ranch near Santa Fe, New Mexico, around 1:50 p.m. local time after receiving a call about a shooting. Hutchins, 42, died after being transported to the University of New Mexico Hospital in critical condition.

The film's director, Joel Souza, 48, left the hospital on Friday morning after also being injured in the incident, a cast member tweeted on Friday. Deadline previously reported that Souza was hit in the shoulder.

"According to investigators it appears that the scene being filmed involved the use of a prop firearm when it was discharged," the sheriff's office said in a statement provided to Insider. "Detectives are investigating how and what type of projectile was discharged."

The investigation is ongoing, and law enforcement is interviewing witnesses. No charges have been filed. Production on the film - a Western set in the 19th century that was developed by Baldwin and Souza, who wrote the screenplay in addition to directing the movie - has also been halted. Movie productions typically use blanks for firearms, and industry guidelines forbid live ammunition.

On Friday, photos published by the Santa Fe New Mexican showed Baldwin in tears and looking distraught outside the sheriff's office.

Hutchins - a graduate of the prestigious American Film Institute who was named a "rising star" by American Cinematographer magazine in 2019 - had recently posted a photo on social media from the set of "Rust."

The caption said she stood in solidarity with the IATSE union, which last week was days away from launching an industry-wide strike over poor working conditions on film and television sets.

The labor union, which represents Hollywood's crew and technical workers, including cinematographers, editors, and hairstylists, called off the strike after announcing a deal with the Alliance of Motion Picture and Television Producers, the trade organization that represents major Hollywood studios, such as Paramount Pictures, Warner Bros., and Universal.

In the post, Hutchins wrote: "Standing in #IAsolidarity with our @IATSE crew here in New Mexico on RUST."

A post shared by Halyna Hutchins (@halynahutchins)