Two Australian miners working deep underground were fatally injured when they fell about 15 meters (50 feet) into a void that had opened beneath them, according to a statement Thursday from mining group Perenti.

The miners – named as Trevor Davis and Dylan Langridge – were working about 125 meters (407 feet) below ground in the Dugald River mine near Cloncurry on Wednesday when the ground gave way.

The hole also swallowed their utility vehicle, a drill rig and the drill rig operator, though that worker was rescued Wednesday with only minor injuries.

The incident prompted an urgent rescue operation that stretched through the night as rescue teams tried to locate the vehicle and cut through rock and earth to reach it.

Perenti managing director and CEO Mark Norwell expressed his condolences to the men’s families on Thursday and said the outcome of the tireless search was “simply not acceptable.”

“This tragic incident is devastating and will have a lasting impact on not only the families and friends of Trevor and Dylan but also on the workforce of Dugald River, the Cloncurry and Mount Isa communities and the entire Perenti workforce,” Norwell said in a statement.

The men were last believed to be on a stope – a tunnel used in mining to ferry materials to the surface – that had previously been filled in with rocks when the void opened, Perenti said earlier.

Drones fitted with cameras were flown into the hole on Wednesday and teams had used scanning technology and video images to locate the vehicle the men – both in their 30s – were believed to have been driving.

On Thursday, rescue teams began trying to reach them from below – the zinc mine has multiple levels, which they hoped would give them better access to the right location.

Before the men were confirmed dead, Cloncurry Mayor Greg Campbell said the incident had come as a shock to residents in the mining hub, which is home to around 3,600 people. Many in the town work in the mines, or know someone who does.

“Dugald mine is fairly new, so it’s definitely the first serious incident that I know of there,” Campbell said. “And over the generations, mining has become much, much safer, so it is quite a rare occurrence to hear of something as serious as this.”

Though information from the mine was limited, Campbell said conditions were likely to be treacherous for rescue teams as they negotiated rocks and other debris, as well as the upended drill rig.

“Trying to shift all that out on the surface would be a job in itself, let alone trying to do it in pitch darkness, in the confined areas of an underground mine where conventional cranes and heavy lift type equipment just can’t access,” he said.

The missing miners were employed by Barminco, a subsidiary of Perenti, and they were working within the mine operated by mining firm MMG, which employs around 500 people at the site.

In a statement Wednesday, MMG said the miners were reported missing at 8:55 a.m. local time on Wednesday and operations at the Dugald River site had since been suspended.

MMG said the mine’s emergency team worked alongside Barminco, emergency services and the Queensland Mines Inspectorate in the rescue operation. The Dugald River mine produces zinc concentrate, with byproducts including lead and silver, MMG says on its website. (CNN)

•PHOTO: The entrance to the underground portal at Dugald River mine is shown in this undated handout photo from MMG. From MMG/FILE

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