Four of the workers are fighting for their life with major burns to their body and a fifth is in a serious condition after being airlifted from Moranbah to hospitals in Brisbane after Wednesday's explosion.
The explosion is believed to be have been set off by a friction event underground.
Anglo American metallurgical business CEO Tyler Mitcheslon said the company still did not know what caused a fire underground at its Grosvenor longwall mine in Queensland on May 6.
"Our focus right now is on supporting our injured colleagues and their families, and our team is doing everything they can to provide support," Mitchelson said.
"We are all devasted and we don't yet understand what caused this incident.
"Once it is safe to return underground, we will commence an expert technical investigation to ensure we understand what has happened.
"We will then work with our regulators and other stakeholders to ensure this type of incident never happens again."
Operations at the Grosvenor site remain suspended, as the company worked with relevant authorities to ensure the mine was safe to return underground to start an investigation into the incident.
Queensland resources minister Dr Anthony Lynham said two mines inspectors were on site yesterday and two more would arrive today, including the deputy chief inspector of mines.
"All other workers are accounted for and operations have ceased," he said.
"Worker safety is in this government's DNA and I expect a thorough independent investigation by the mine safety regulator."
Queensland Resources Council CEO Ian Macfarlane said no-one knew precisely what happened at the Grosvenor mine.
He said the Mines Inspectorate was undertaking a full investigation and it would make its findings available.
"No-one should pre-empt those findings," Macfarlane said.
"On behalf of the industry, I told mines minister Dr Anthony Lynham the Inspectorate will have our support and cooperation."
More than 100 industry representatives joined the Queensland mining industry's regular COVID-19 teleconference update yesterday.
Macfarlane said on that call, the industry reaffirmed its commitment to the priority of safety for all.
"The Queensland Resources Council and its member companies have worked with the government and unions on the expert reports into mine safety following the tragic loss of six lives since July 2018," he said.
"Dr Lynham has reaffirmed his commitment to work with us."
Australian resources minister Keith Pitt added his concern for the injured workers and their families.
"This is a distressing time for the Queensland mining community, particularly the workmates of the injured workers at the mine site," he said.
"I have spoken with Queensland minister Anthony Lynham who informed me an official investigation is now underway to determine the cause of the accident."
