Rescuers dug with heavy machinery Thursday to find two men trapped for more than 24 hours after a utility vehicle plunged down a "void" in a remote Australian zinc mine.
The missing pair are believed to be 125 metres (400 feet) below ground after their light utility vehicle fell down an ore extraction tunnel within the Dugald River mine in Queensland, the owners said. Using drones, scanning technology and video imagery, searchers had located the vehicle in the shaft, they said.
Rescuers had worked through the night with heavy underground mining equipment to try to reach the vehicle, according to a statement by Perenti Group, the parent group of mine owner MMG.
"Whilst we hold deep concerns for the safety of our colleagues, we continue to be hopeful that a positive outcome can be achieved," said Perenti chief executive Mark Norwell.
The men have been identified in local media as Dylan Langridge and Trevor Davis.
"Our approach today is to continue to safely remove material from around the vehicle so we can safely extract it," said MMG general manager Tim Akroyd.
Rescuers aimed to reach the vehicle from below, the mine said. The accident occurred Wednesday morning when two vehicles -- the light utility vehicle and a drill rig -- fell into a "void" in a previously filled-in ore excavation shaft below ground, it said.
The two missing men were believed to be in the trapped light utility vehicle. A third man, who was in the drill rig, was rescued Wednesday and treated for minor injuries.
The Dugald River mine employs some 500 people near the isolated town of Cloncurry in western Queensland, about 20 hours' drive inland from the state's capital of Brisbane.
According to MMG, which is listed on the Hong Kong Stock Exchange, Dugald River processes some 1.7 million tonnes of ore every year.
Mining is one of the bedrocks of Australia's economy -- the country holds almost 30 percent of the world's reserves of zinc, lithium and nickel.
Studies have found Australia's mining sector is one of the safest by international standards -- but according to the government it is still the third deadliest industry in the country.