A report into the fatal shooting of cinematographer Halyna Hutchins on the set of movie Rust has found the production company “knew that firearm safety procedures were not being followed on set” and “demonstrated plain indifference to employee safety”.

Rust Movie Productions has been given a fine of 136,793 US dollars (£104,810), the maximum allowable by state law in New Mexico, following a six-month investigation by the state’s environment department.

Ms Hutchins was killed on the set of the Western movie in October last year after a prop gun actor Alec Baldwin was holding was discharged.

Director Joel Souza was also wounded in the shooting on the Bonanza Creek Ranch set near Santa Fe.

Baldwin’s lawyers say they are “grateful” to the New Mexico occupational health and safety bureau, saying the report “exonerates” the actor.

The report concluded the company showed “plain indifference to the recognised hazards associated with the use of firearms on set that resulted in a fatality, severe injury, and unsafe working conditions”.

It also noted that while the film industry has “clear national guidelines” for firearms safety, Rust Movie Productions “failed to follow these guidelines or take other effective measures to protect workers”.

The guidelines require live ammunition “never to be used nor brought onto any studio lot or stage” and that safety meetings take place every day when firearms are being handled.

They also requires that employees “refrain from pointing a firearm at anyone” except after consultation with senior figures such as the armorer.

But the report concludes: “By failing to follow these practices, an avoidable loss of life occurred.”

A statement from Baldwin’s lawyers, posted by the actor on Twitter, said: “We are grateful to the New Mexico occupational health and safety bureau for investigating this matter.

“We appreciate that the report exonerates Mr Baldwin by making clear that he believed the gun held only dummy rounds.

“Additionally, the report recognises that Mr Baldwin’s authority on the production was limited to approving script changes and creative casting.

“Mr Baldwin had no authority over the matters that were the subject of the bureau’s findings of violations, and we are pleased that the New Mexico officials have clarified these critical issues.

“We are confident that the individuals identified in the report will be held accountable for this tragedy.”

It comes as the Hollywood actor continues to fight a number of lawsuits stemming from the incident.

Cases are being brought by script supervisor Mamie Mitchell, head of lighting Serge Svetnoy and Ms Hutchins’ family.

As well as Baldwin, two of the lawsuits name nearly two dozen defendants associated with the film, including Hannah Gutierrez Reed, who was in charge of weapons on the set.

Lawyers for Gutierrez Reed said the report also showed that the armourer was “not provided adequate time or resources to conduct her job effectively, despite her voiced concerns”.

“Critically, OSHA also determined that production failed to call Hannah in to perform her armorer duties and inspect the firearm right before its use in the impromptu scene with Baldwin,” they said in a statement.

“As we have stated before, had anyone from production called Hannah back into the church before the scene to consult with her, this tragedy would have been prevented.

“Hannah has also reached out to OSHA recently in an effort to provide her suggestions for changes and improvement of safety standards on sets to avoid a tragic incident in the future.”

Environment cabinet secretary James Kenney said: “Our investigation found that this tragic incident never would have happened if Rust Movie Productions, LLC had followed national film industry standards for firearm safety.

“This is a complete failure of the employer to follow recognised national protocols that keep employees safe.

“Employees should speak up about unsafe workplace conditions or report them anonymously to us.”

Robert Genoway, chief of the New Mexico environment department’s occupational health and safety bureau, said: “As a reminder, it is illegal for any employer to retaliate against any employee who alleges a workplace safety violation.”

The bureau said the investigation involved 1,560 hours of staff time, 14 interviews and review of 566 documents.

In January, Baldwin surrendered his mobile phone to authorities as part of the inquiry.

In the wake of the shooting, production on Rust was halted indefinitely while authorities investigated.

In his first interview following the incident, Baldwin told Good Morning America he was dreaming about the incident “constantly”, adding: “I couldn’t give a shit about my career any more.”

He also said he cocked the gun that killed Hutchins but “didn’t pull the trigger”.

In February, Baldwin was in the UK filming for what reports said was the air disaster thriller 97 Minutes.