'Heartbreaking': Premier speaks after two killed in NSW mine explosion

Premier Chris Minns has called for ongoing vigilance in workplace safety after two people died in an explosion in an underground mine in far western New South Wales early this morning.

Emergency services were called to the mine on Endeavor Mine Road, Cobar, about 450km east of Broken Hill, about 3.45am, after reports two people were critically injured in a workplace incident.

On arrival, police were told a man had been confirmed dead after an underground explosion.

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Two women were brought to the surface, however, one has since died.

The second woman has been airlifted to hospital after suffering hearing damage and shock.

The man is believed to have been in his 60s, the two women in their 20s.

They have not yet been formally identified but it's believed all three lived in Cobar, police said.

Emergency services remain at the scene.

"There has obviously been a catastrophic failure of a safety system at the mine," Bob Timbs from the Mining and Energy Union said.

"At this day and age, that type of accident should just not have happened."

The NSW Mineworkers Alliance said the union was "in shock" over the deaths.

"We will leave no stone unturned in identifying what has occurred here," spokesperson Tony Callinan said.

"This is a tragic reminder that underground mining is a dangerous job."

The union pledged to provide support to workers at the site.

"We extend our deepest condolences to the family, friends and colleagues of the workers who have tragically died in Cobar today," Minns said.

"This is a heartbreaking day for the Cobar community and will be felt across the entire mining industry."

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Minns said safety was the "number one priority" in any mine.

"Everyone who goes to work has the right to come home," he said.

"While safety protocols and procedures have greatly improved in mining, these deaths are a sobering reminder of why we need to always remain vigilant to protect workers."

NSW Minerals Council chief executive Stephen Galilee has also addressed the tragedy.

"The thoughts of tens of thousands of miners across NSW will today be with the families and colleagues of the deceased and injured, and also with the residents of the mining community of Cobar at this extremely difficult time," he said.

Police will prepare a report for the coroner and assist SafeWork NSW with the investigation.

Endeavor is a silver, zinc, and lead mine that operated from 1982 to 2020, and which was recently purchased by new owners Polymetals, who sought to restart production this year.

Polymetals this morning announced a pause in trading on the ASX pending a further announcement.

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