Alec Baldwin has expressed his deep “shock and sadness” after he accidentally shot and killed his director of photography with an apparent real bullet while on the set of his latest movie.

The actor was acting in or rehearsing for the western Rust when he discharged what he thought was a prop firearm. The cinematographer Halyna Hutchins was fatally struck and the director Joel Souza was wounded, Santa Fe sheriff’s office said.

Despite attempts to save her, Hutchins was pronounced dead after being flown by helicopter to the University of New Mexico hospital. Souza was being treated at Christus St Vincent regional medical centre, where he was brought by ambulance.

On Friday, Baldwin tweeted: “There are no words to convey my shock and sadness regarding the tragic accident that took the life of Halyna Hutchins, a wife, mother and deeply admired colleague of ours. I’m fully cooperating with the police investigation to address how this tragedy occurred.”

The Hollywood actor said he was in touch with Hutchins’ husband, Matthew, with whom she has a young son. “[I’m] offering my support to him and his family. My heart is broken for her husband, their son, and all who knew and loved Halyna,” Baldwin said.

The sheriff’s office said no charges had been brought following what appeared to be a tragic accident. The 68-year-old actor went “voluntarily” to the Santa Fe county office and spoke with investigators, spokesperson Juan Rios said.

The incident happened at 1.50pm local time on Thursday. Baldwin was spotted in the parking lot outside the sheriff’s building, speaking on the phone and visibly upset, the Santa Fe New Mexican newspaper reported.

Detectives are likely to examine why the prop gun went off with such catastrophic consequences. In an email to its members on Friday, the entertainment union IATSE claimed the gun had contained a “single live round”. The weapon was “accidentally fired” by the “principal actor”, it added.

One Hollywood website, quoting a witness, said a distraught Baldwin had asked why he had been given a firearm apparently loaded with real ammunition. “In all my years, I’ve never been handed a hot gun,” he exclaimed, according to the site, Showbiz 411.

Production on the western has been indefinitely halted, its producers said on Friday. The film was being shot in Bonanza Creek Ranch, a purpose-built set featuring log cabins, an authentic wooden church and an arid brown landscape, in the foothills of northern New Mexico.

The location, popular with film-makers, was the period setting for Tom Hanks’s 2020 film, News of the World. Rust, set in 1880s Kansas, tells the story of a 13-year-old boy who is left to fend for himself and his younger brother after the death of their parents. Baldwin plays the boy’s grandfather.

The actor was also producing the movie, while Souza directed and wrote the script. Hutchins, who was born in Ukraine, was director of photography. Friends on Friday praised her warmth, energy and collegiality, and said she had reached the top of a traditionally male-dominated profession.

Friend and fellow film-maker Elle Schneider told BBC Radio 4’s World at One programme that Hutchins was a “talented, dedicated artist”.

Schneider added: “She was just as invested in her friends success as she was in her own. She was just incredibly passionate about her work, collaborators, and friends, and fellow women coming up alongside her. She was fun to be around. She had an energetic and magnetic personality.”

“I’m so sad about losing Halyna. And so infuriated that this could happen on a set,” said Adam Egypt Mortimer, a director who had worked with Hutchins last year on the film Archenemy. “She was a brilliant talent who was absolutely committed to art and to film.”

Earlier this week, Hutchins posted pictures from the New Mexico set including a short video clip that showed her riding a horse together with other crew members. “One of the perks of shooting a western is you get to ride horses on your day off,” she wrote.

Another image taken on Wednesday reveals her standing next to Baldwin, who is dressed in a cowboy outfit. The actors and crew had broken off from filming to express solidarity with the entertainment union IATSE, which had demanded better pay and conditions, she wrote on Instagram.

According to her website, Hutchins grew up on a Soviet military base in the Arctic Circle surrounded “by reindeer and nuclear submarines”. An “army brat”, she became interested in film because there was “nothing much else to do”, she said. She cited the 1957 Soviet war film The Cranes Are Flying as an influence.

After taking a graduate degree in international journalism from Kyiv National University in Ukraine, Hutchins worked with British documentary productions, shot in remote locations in eastern Europe, and became increasingly fascinated with cinematography.

Later she dedicated herself to film-making and moved to the US, where she lived with her lawyer husband, Matthew, and their son. Hutchins took production assistant jobs and “dabbled” in fashion photography, and studied from 2013-15 at the American Film Institute in Los Angeles.

She rose rapidly and in 2019 was named a “rising star” by American Cinematographer.

“The details are unclear … but we are working to learn more, and we support a full investigation into this tragic event,” the International Cinematographers Guild’s president, John Lindley, and executive director Rebecca Rhine said.

Accidents like those that befell Hutchins have happened before. In 1993, Brandon Lee, the 28-year-old son of the late martial arts star Bruce Lee, died after being hit by a .44-calibre slug while filming a death scene for the movie The Crow. The gun was supposed to have fired a blank, but an autopsy turned up a bullet lodged near his spine.

Before the shooting, Baldwin posted a picture of himself on Instagram sporting a grey beard and dressed in western cowboy-style outfit. He appeared to have a fake bloodstain on his shirt and jacket. “Back to in person at the office. Blimey … it’s exhausting,” he wrote. The post was deleted late on Thursday night.

Known for his impersonations of Donald Trump on NBC’s comedy sketch show Saturday Night Live, Baldwin has a long history in film and television, including roles in Glengarry Glen Ross and 30 Rock.

Baldwin was charged in 2018 after a fight over a New York parking spot. He pleaded guilty to second-degree harassment and agreed to participate in an anger management programme.

In 2014, he was given a summons for disorderly conduct after an argument with police, who stopped him from riding his bike down a one-way street in New York. In 2011, he was thrown off a plane for refusing to stop playing the game Words With Friends before take-off.

Souza, 48, lives in the San Francisco Bay Area with his wife and two children, according to the IMDB website. His LinkedIn page credits him as the writer/director of action film Crown Vic and the comedy Christmas Trade.

“This is still an active investigation and we do not yet have all the facts,” said Sag-Aftra, which describes itself as the world’s biggest union representing performers and broadcasters.

“We will continue to work with production, the other unions, and the authorities to investigate this incident and to understand how to prevent such a thing from happening again.”