Alec Baldwin on set after the death of cinematographer Halyna Hutchins at the Bonanza Creek Ranch in Santa Fe, New Mexico
Alec Baldwin on set after the death of cinematographer Halyna Hutchins at the Bonanza Creek Ranch in Santa Fe, New Mexico AFP

Alec Baldwin is to be charged with involuntary manslaughter over the accidental shooting of a cinematographer on the set of the low-budget western "Rust," a prosecutor said Thursday.

Baldwin was holding the Colt. 45 during rehearsals for the film when it discharged, killing Halyna Hutchins and wounding director Joel Souza in October 2021.

The film's armorer, Hannah Gutierrez Reed, who was responsible for the weapon, will also be charged with the same crime, New Mexico First Judicial District Attorney Mary Carmack-Altwies announced.

If convicted, they both face up to 18 months in jail and a $5,000 fine.

"After a thorough review of the evidence and the laws of the state of New Mexico, I have determined that there is sufficient evidence to file criminal charges against Alec Baldwin and other members of the 'Rust' film crew," Carmack-Altwies said.

"On my watch, no one is above the law, and everyone deserves justice."

Baldwin has repeatedly said he was told by crew that the gun was not loaded.

The former "30 Rock" star has also previously said he did not pull the trigger, though experts have cast doubt on this claim.

Assistant director David Halls, who handed Baldwin the weapon and told him it was "cold" -- industry speak for safe -- has agreed to plead guilty to negligent use of a deadly weapon.

He will serve a suspended sentence and six months of probation, a statement said.

No charges will be filed over the injury to Souza.

A lengthy investigation has looked at how the live round -- and five others -- got onto the New Mexico film set, with attention focused on the armorer and ammunition supplier.

Investigators found Gutierrez Reed had put the fatal round in Baldwin's gun, instead of using a similar-looking dummy round.

Detectives probing the tragedy spoke of a lax attitude to safety on the set, and crew members have subsequently claimed that corners were cut.

The accident sent shockwaves through Hollywood and led to calls for a total ban on the use of real guns on set.

Industry experts have said there are already stringent safety rules in place and that the only way for an accident like this to have happened was for them to have been ignored.

Baldwin last year reached an undisclosed settlement with the family of 42-year-old Hutchins.

It was also announced at the time that production on the low-budget movie would restart this year.

Widower Matthew Hutchins, who will become an executive producer, said "all the original principal players" would return to the set.

Souza said he would devote his work on the film "to honoring Halyna's legacy and making her proud."