Kazakhstan has confirmed the nationalisation of ArcelorMittal Temirtau – which operates the country’s largest steel plants and several coal and ore mines – following a coal mine fire that killed at least 32 workers while another 14 remain unaccounted for.

Some 252 people were working at the Kostenko coal mine in the Karaganda region at the time of the blaze, officials said.

It is believed the fire was caused by a pocket of methane gas.

The fire is the latest in a string of workplace deaths at sites operated by ArcelorMittal Temirtau.

In August, four miners were killed after a fire erupted at the same mine while five people died following a methane leak at another site in November 2022.

The company confirmed on Saturday it was finalising a deal with the Kazakh government to nationalise the firm amid growing discontent from officials.

Prime Minister Alikhan Smailov said in a statement on the Kazakh president’s website that the government had reached a preliminary agreement with the company’s shareholders and was now in the process of “formalising” the nationalisation.

Speculation around the company’s future had been growing since September, when Kazakhstan’s first deputy prime minister Roman Sklyar told journalists the government had started talks with potential investors to buy out ArcelorMittal after becoming increasingly unhappy with its failure to meet investment obligations and repeated worker safety violations.

Speaking on Saturday, Kazakh President Kassym-Jomart Tokayev announced October 29 as a national day of mourning.

The office of the country’s Prosecutor General has also said it was starting an investigation into potential safety violations in the coal mine.

ArcelorMittal Temirtau said work had been halted at all of their coal mining sites in Kazakhstan.

It also conveyed “pain” at the lives lost and said its efforts “are now aimed at ensuring that affected employees receive comprehensive care and rehabilitation, as well as close co-operation with government authorities.”

ArcelorMittal Temirtau is the local representative for Luxembourg-based multinational ArcelorMittal, the world’s second-largest steel producer.