Exxaro reported that the strike action across its Matla, Arnot, Grootegluk, Leeuwpan, Inyada and Reductants mines persisted despite continued engagement with the National Union of Mineworkers.

In the latest meeting between the two parties Exxaro’s eight point proposal, which included the one-off offer of R2000 to end the strikes, was rejected.

In a statement the company said the central issue of the strikes was the non-payment of performance incentives, which Exxaro claimed were not paid because performance standards were not met.

NUM confirmed that although it did not initiate the unprotected strikes, its members were participating.

The union suggested Exxaro issue an across-the-board one-off payment to end the strike.

Exxaro said escalating violence encouraged the company to obtain a court order to stop the strike but there was no indication yet whether workers would comply.

“Exxaro reiterates the call for striking employees to return to work,” a company statement said.

“The ‘no work, no pay’ principle applies and it is in the best interests of striking employees to resume their normal duties as soon as possible.”

Police on Monday fired rubber bullets at a group of about 2000 strikers at the Grootegeluk mine, Reuters reported.

Police spokesman Ronel Otto said protesters had hijacked two trucks and blocked roads.

Often-violent labour unrest shut parts of South Africa's mining industry for months last year and the industry remains anxious about a renewal of the disturbances that left more than 50 people dead and pushed prices higher.

The stoppage of production at the affected mines also puts pressure on state utility Eskom, which uses coal to generate 85% of South African electricity.

Exxaro is the second-largest supplier of coal to Eskom and there are fears the strikes could eventually lead to an electricity shortage and blackouts.