A delicate recovery operation is set to begin today to bring out the bodies of two coal miners killed in an underground mine collapse.
But police have warned it could take several days to retrieve the bodies from the NSW Hunter Valley mining operation.
Eight miners were working 500m below and 10km along the Austar Coal Mine when a wall collapsed and trapped two men at about 9.15pm yesterday.
The other miners tried to save their workmates before having to leave the mine because of safety fears.
A rescue mission was launched at the mine at the small village of Paxton, but both men were pronounced dead just after midnight.
One man was a 35-year-old from Metford and the other a 49-year-old from Cessnock, with police expecting to release their names later on Wednesday.
"Two local men. A tragic incident for all people involved, the co-workers and families of the men. It is close-knit community and will be traumatic to many families," Superintendent Garry O'Dell said.
Supt Dell said safety issues and the difficult location of the accident meant it was going to be challenging to retrieve the bodies.
He said it could take a number of days,.
"There is a fair bit of equipment and coal in the area that needs to be removed to be able to get access to them," he said.
All mining production has been stopped at the site.
Supt Dell said police had spoken briefly with the other miners who were at the accident scene.
"The general manager of the mine informed all the workers this morning of what has occurred and it is tragic for all person involved," he said.
Police and specialist mine investigators are continuing their inquiries.
NSW Resources Minister Anthony Roberts said lessons had to be learnt from the accident.
"I would like to personally extend my condolences to the families, co-workers and employers of those involved in this tragic incident," he said.
Local federal MP Joel Fitzgibbon expressed his condolences via social media.
"Thoughts & prayers for the Austar miners, their families, loved ones and mates," he tweeted.
"A shocking tragedy. And to the local families who will send a loved one to a mine today and tonight. Mine safety must never be a traded commodity."
