Alec Baldwin was handed a weapon loaded with live ammunition by an unwitting assistant director who yelled "cold gun" in the moments before the actor fatally shot a cinematographer, police said.
New details of how the tragedy unfolded emerged in an affidavit filed late on Friday in a New Mexico court by the Santa Fe County Sheriff's Office.
According to the affidavit the gun involved was one of three that the armourer for the movie Rust had set on a cart outside a wooden structure where a scene involving Baldwin was to be filmed.
An assistant director picked up the gun from the cart and brought it inside the building to Baldwin. The assistant director was unaware that it was loaded with live rounds, according to the warrant.
When Baldwin pulled the trigger cinematographer Halyna Hutchins, 42 was fatally shot, and director Joel Souza, 48, was injured.
Hutchins was hit in the chest, and Souza, who was standing behind her, was hit in the shoulder, the warrant said.
The Sheriff's Office said it was seeking evidence including the weapon, Baldwin's "Old Western Style" costume which appeared to have blood stains, other prop guns and ammunition, and any footage that had been filmed.
It was still unclear whether the tragedy happened while cameras were rolling.
The affidavit by Detective Joel Cano said the incident occurred during a rehearsal, but there was film equipment there.
The detective said he "would like to confirm if the incident that took place was or wasn't recorded."
Detailing what happened he wrote: "As the assistant director handed the gun to the actor Alec Baldwin, (the assistant director) yelled 'cold gun', indicating the prop gun did not have any live rounds."
While the investigation progresses the heartbroken husband of Hutchins has revealed his "enormous loss" after his "inspiring" wife was shot dead.
Matt Hutchins posted a picture of Halyna and her 8-year-old son Andros with an emotional tribute saying "our loss is enormous".
Her distraught family in the Ukraine were yesterday demanding answers about her death as they frantically tried to to fly to the US.
Friends said dad Antoly and mum Olga were "beside themselves with grief" after being told of the tragedy.
"The family is grieving but at the same time they are asking and they will want answers. If someone made a mistake then they will have to pay," the friend said. "They just don't understand how something dreadful like this could have happened when safety measures are supposed to be in place.
"They are also frantically trying to secure documents to get to the United States. Her mother does not have the correct paperwork," they said.
Film studio bosses are also worried of a major lawsuit from the family.
Meanwhile, questions were raised about working conditions on the set of Rust.
The small budget Western movie, of which Baldwin was both star and a co-producer, was being filmed at the Bonanza Creek Ranch. Both the Los Angeles Times and Deadline Hollywood reported that half a dozen of the camera crew had walked off the set hours before the tragedy over working conditions.
The Los Angeles Times reported that there had been a previous accidental prop gun discharge involving Baldwin's stunt double.
A crew member told the newspaper: "There should have been an investigation into what happened."
According to Deadline one of the camera crew who walked off set posted on Facebook: "We cited everything from lack of payment for three weeks, taking our hotels away despite asking for them in our deals, lack of Covid safety, and on top of that, poor gun safety! Poor on-set safety period!"
The Los Angeles Times reported that the crew members who left were members of the International Alliance of Theatrical Stage Employees and were replaced with non-union crew.
In a statement Rust Movie Productions said: "Though we were not made aware of any official complaints concerning weapon or prop safety on set, we will be conducting an internal review of our procedures while production is shut down.
"We will continue to cooperate with the Santa Fe authorities in their investigation and offer mental health services to the cast and crew during this tragic time."
A distraught Baldwin described how his "heart is broken" and there were "no words to convey his sadness."
The actor said he was doing all he could to support the family of Hutchins. Baldwin, 63, paid tribute to "a wife, mother and deeply admired colleague of ours".
He added: "My heart is broken for her husband, their son, and all who knew and loved Halyna." Baldwin was reported to have repeatedly asked afterwards why he had been given a "hot gun".
The Departed star said he was fully cooperating with police to investigate "how this tragedy occurred".
In a 911 emergency call, published by the website TMZ and yet to be independently verified, a woman who identified herself as a script supervisor said: "We have two people accidentally shot on a movie set by a prop gun. We need help immediately. We need some help. Our director and a camerawoman have been shot."
The dispatcher asked if the gun was loaded with a real bullet. The script supervisor said: "I cannot tell you that. We have two injuries from a movie gun. Shot. I was sitting, we were rehearsing, and it went off and I ran out. We all ran out. They were doubled over...the camerawoman and the director."
Gun safety protocol on sets in the US has dramatically improved since an on-set accident in 1993 which left Brandon Lee, son of the late martial-arts star Bruce Lee, dead after he was hit by a bullet left in a prop gun.