Two people are dead and another is in hospital after an underground mine explosion in far-west NSW.

Emergency services were called to the incident on Endeavor Mine Road at Cobar, some 450 kilometres east of Broken Hill, about 3.45am on Tuesday.

Police were immediately told a man in his 60s had been confirmed dead after the underground explosion.

Two women in their 20s were then brought to the surface, but one died shortly after.

The second was flown to hospital in Orange suffering hearing damage and shock. She was in a stable condition later on Tuesday.

About 7.15am, NSW Police confirmed the deaths and said emergency services remained at the scene.

Police said both women and the man were from Cobar, about 40 kilometres south of the Endeavor Mine.

The explosion occurred at the Endeavor site, a major underground silver, zinc and lead mine. Image: Polymetals

SafeWork NSW will lead an investigation into the incident, with police to also prepare a report for the coroner. Police will also work with specialists from the NSW Resources Regulator.

Cobar mayor Jarrod Marsden said he was struggling to come to terms with the deaths, and the town would need to find strength in community to get through the tough time.

“Two families’ loved ones didn’t come home from a night shift. Their lives have been changed forever, just decimated by this,” he said.

“We’re devastated, just in shock and it’s impossible to try to find the words to describe it.”

Local MP Roy Butler said the deaths would be felt “deeply and widely”.

NSW Premier Chris Minns also offered his condolences to the workers’ families and workmates.

“This is a heartbreaking day for the Cobar community and will be felt across the entire mining industry,” he wrote on social media.

“The No.1 priority in any mine must be safety. Everyone who goes to work has the right to come home.”

NSW Mineworkers’ Alliance spokesman Tony Callinan called for an open and transparent investigation into how the accident happened.

“We will leave no stone unturned in identifying what has occurred here,” he said.

“This is a tragic reminder that underground mining is a dangerous job … events like these send shockwaves through our entire mining industry.”

NSW Minerals Council chief Stephen Galilee agreed the tragedy highlighted that safety must always be top priority on sites.

“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.

The Endeavor Mine is a major underground silver, zinc and lead mine. It’s the second largest project in the polymetallic region known as the Cobar Basin.

The mine was acquired by Polymetals in 2024 and planned to restart mining activities earlier this year.

Copper and gold mining are the two leading employment industries in the isolated region. The wider Cobar region has a population of about 4700.

Polymetals requested trading in its shares be paused for two days after a “serious safety incident” but it did not otherwise comment on the deaths.

It is not the first fatal mining accident in Cobar.

A cave-in in 1971 killed four miners, while a shaft fire in 1980 led to the deaths of another three.

-with AAP