Falling rocks inside a gold mine in Australia killed one worker and left another with life-threatening injuries, rescuers have said.

Another 29 workers inside the mine when the collapse happened on Wednesday took refuge in a safety pod and later returned to the surface, Victoria state police said.

The two miners were trapped by the falling rocks late in the afternoon about 1.9 miles underground in the Ballarat Gold Mine, north west of Melbourne.

A 21-year-old worker needed emergency medical treatment for lower body injuries before he could be removed from the mine about four hours later and was airlifted to a hospital, police said in a statement.

The body of the 37-year-old man who died was recovered by mine rescue personnel on Thursday morning.

The mine has been shut down, and the state police said they would prepare a report for the coroner, while the local safety regulator also will investigate.

Federal Minister for Resources Madeleine King told ABC Radio it was too early to know what happened.

“Our members have raised concerns about this style of mining and it seems to have fallen on deaf ears,” Australian Workers Union Victoria state secretary Ronnie Hayden said.

The two workers were drilling into the rock manually using an “air legging” technique that was new to the site and were on unsupported ground, he said. Air legging is a method of drilling that penetrates the rock with air and water.

“This form of air legging should not be used to do this type of work,” he said.

The mine’s owner Victory Minerals, which took ownership of the mine in December, said it was a “safety-first mine operator” and was working closely with emergency authorities and safety regulators.

“Right now our priority is the safety and well-being of our mining workers and their families,” it said in a statement.

At the same mine in 2007, a rock collapse trapped 27 miners underground for several hours before they were rescued.