The death toll of the miners killed at the Phalaborwa Copper Mine in Limpopo has risen to six.
The National Union of Mineworkers' north east regional secretary Phillip Mankge confirmed the latest fatality to News24.
The deaths come after a fire broke out at the mine in the early hours of Sunday.
The fire reportedly started at conveyor belt five, and when smoke was seen by a logistic belt operator, the workers were instructed to evacuate the area to the closest refuge chamber, the union said on Sunday.
NUM said it would, together with Cosatu's provincial secretary in Limpopo, Gerald Thwala, meet to establish the root cause of the incident.
"As the NUM, we vehemently condemn this kind of incident as there is a high number of fatalities in the mining industry in South Africa this year," the union said in a statement.
The union has urged the department of mineral resources to play a role in ensuring that mines are safe and to make the safety of the mineworkers a priority.
It also demanded an immediate investigation by the department to establish the cause of the incident at the mine.
"We call upon employers to put lives of mineworkers first so that we can be able to achieve zero harm and zero death in the mining industry."
The union added and said the fact that there was no improvement on the fatal mining accidents could only be interpreted as a sign of a "lack of commitment toward zero harm and zero death by the mining sector".
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